{
  "title": "European megalith transport gazetteer",
  "version": "0.4.1",
  "updated": "2026-09-13",
  "license": "CC BY-SA 4.0 Tim Daw",
  "distance_note": "km_used is the published working figure plotted on the map. Sector centroids are midpoints of a published search area.",
  "hauls": [
    {
      "id": "GMB-orthogneiss",
      "site": "Grand Menhir Brise d'Er Grah",
      "site_lat": 47.57194,
      "site_lon": -2.95056,
      "source": "Orthogneiss sector Auray / Ste-Anne-d'Auray / Clehuer",
      "source_lat": 47.665,
      "source_lon": -2.983,
      "source_precision": "sector-centroid",
      "rock": "Orthogneiss",
      "mass_t": 300,
      "km_min": 4,
      "km_max": 12,
      "km_used": 10,
      "mode": "overland / ria",
      "evidence": "high",
      "method": "Petrography and bedrock mapping; southern Brittany ice-free",
      "refs": [
        "Le Roux 1998",
        "Sellier 1995",
        "Le Roux et al. 2006"
      ],
      "region": "Brittany"
    },
    {
      "id": "GAV-refit",
      "site": "Gavrinis capstone (refit)",
      "site_lat": 47.5712,
      "site_lon": -2.8984,
      "source": "Broken Locmariaquer orthogneiss stele",
      "source_lat": 47.5717,
      "source_lon": -2.9495,
      "source_precision": "named-monument",
      "rock": "Carved orthogneiss",
      "mass_t": 20,
      "km_min": 3.5,
      "km_max": 4.5,
      "km_used": 4,
      "mode": "water",
      "evidence": "high",
      "method": "Physical refit plus matching pecked motifs",
      "refs": [
        "Cassen et al. 2005"
      ],
      "region": "Brittany"
    },
    {
      "id": "DIS-chemoulin",
      "site": "Tumulus de Dissignac",
      "site_lat": 47.2736,
      "site_lon": -2.2769,
      "source": "Pointe de Chemoulin / Batz peninsula facies",
      "source_lat": 47.232,
      "source_lon": -2.299,
      "source_precision": "sector-centroid",
      "rock": "Coastal granite and metamorphic facies",
      "mass_t": null,
      "km_min": 6,
      "km_max": 10,
      "km_used": 8,
      "mode": "overland / coastal",
      "evidence": "medium",
      "method": "Facies matching (L'Helgouach 1976)",
      "refs": [
        "L'Helgouach 1976"
      ],
      "region": "Brittany"
    },
    {
      "id": "BAR-sterec",
      "site": "Cairn de Barnenez",
      "site_lat": 48.6675,
      "site_lon": -3.8594,
      "source": "Ilot Sterec granites",
      "source_lat": 48.676,
      "source_lon": -3.853,
      "source_precision": "named-outcrop",
      "rock": "Granite (two varieties)",
      "mass_t": null,
      "km_min": 1.1,
      "km_max": 1.2,
      "km_used": 1.2,
      "mode": "overland (not then an island)",
      "evidence": "high",
      "method": "Named quarry lithologies (Chauris / Giot)",
      "refs": [
        "Giot Barnenez reports",
        "Chauris identifications"
      ],
      "region": "Brittany"
    },
    {
      "id": "BAR-stsamson",
      "site": "Cairn de Barnenez",
      "site_lat": 48.6675,
      "site_lon": -3.8594,
      "source": "Saint-Samson foreshore leucogranite",
      "source_lat": 48.661,
      "source_lon": -3.825,
      "source_precision": "named-outcrop",
      "rock": "Porphyritic leucogranite",
      "mass_t": null,
      "km_min": 1.9,
      "km_max": 2.5,
      "km_used": 2.2,
      "mode": "overland / foreshore",
      "evidence": "high",
      "method": "Named quarry lithologies (Chauris / Giot)",
      "refs": [
        "Giot Barnenez reports"
      ],
      "region": "Brittany"
    },
    {
      "id": "BOU-bathonian",
      "site": "Tumulus de Bougon",
      "site_lat": 46.3739,
      "site_lon": -0.0647,
      "source": "Bathonian flinty limestone quarry ~4 km",
      "source_lat": 46.36,
      "source_lon": -0.015,
      "source_precision": "sector-centroid",
      "rock": "Bathonian limestone",
      "mass_t": 90,
      "km_min": 3.5,
      "km_max": 4.5,
      "km_used": 4,
      "mode": "overland",
      "evidence": "medium",
      "method": "Lithology versus plateau quarries; 1979 haul experiment",
      "refs": [
        "Mohen Bougon programme"
      ],
      "region": "West-central France"
    },
    {
      "id": "MEN-cruz",
      "site": "Dolmen de Menga",
      "site_lat": 37.02417,
      "site_lon": -4.54861,
      "source": "Cerro de la Cruz quarry",
      "source_lat": 37.0265,
      "source_lon": -4.5595,
      "source_precision": "named-outcrop",
      "rock": "Calcarenite / calcirudite",
      "mass_t": 150,
      "km_min": 0.85,
      "km_max": 1.0,
      "km_used": 0.9,
      "mode": "overland downhill then into trenches",
      "evidence": "high",
      "method": "Microfacies, biostratigraphy, 1:25k mapping",
      "refs": [
        "Lozano Rodriguez et al. 2023"
      ],
      "region": "Andalusia"
    },
    {
      "id": "SOT-candon",
      "site": "Dolmen de Soto",
      "site_lat": 37.3422,
      "site_lon": -6.7375,
      "source": "Candon greywacke / western Sierra Morena suite",
      "source_lat": 37.385,
      "source_lon": -6.73,
      "source_precision": "sector-centroid",
      "rock": "Greywacke (plus quartzite, volcanic)",
      "mass_t": null,
      "km_min": 5,
      "km_max": 35,
      "km_used": 12,
      "mode": "overland",
      "evidence": "high",
      "method": "Petrography and XRF; stela reuse",
      "refs": [
        "Linares-Catela et al. 2021",
        "Linares-Catela and Mora Molina 2018"
      ],
      "region": "Andalusia"
    },
    {
      "id": "ZAM-pluton",
      "site": "Anta Grande do Zambujeiro",
      "site_lat": 38.53917,
      "site_lon": -8.01417,
      "source": "Evora pluton porphyritic granite tors",
      "source_lat": 38.555,
      "source_lon": -8.04,
      "source_precision": "sector-centroid",
      "rock": "Porphyritic granite",
      "mass_t": null,
      "km_min": 2,
      "km_max": 5,
      "km_used": 3.5,
      "mode": "overland upslope",
      "evidence": "medium",
      "method": "Pluton granite differentiation",
      "refs": [
        "Rocha and Bueno-Ramirez 2014"
      ],
      "region": "Alentejo"
    },
    {
      "id": "MAT-cabezas",
      "site": "Matarrubilla basin, Valencina",
      "site_lat": 37.412,
      "site_lon": -6.047,
      "source": "Gypsiferous cataclasite, Las Cabezas de San Juan shore",
      "source_lat": 36.9817,
      "source_lon": -5.9394,
      "source_precision": "named-sector",
      "rock": "Gypsiferous cataclasite",
      "mass_t": 2.1,
      "km_min": 50,
      "km_max": 60,
      "km_used": 55,
      "mode": "water (palaeo-estuary) then uphill",
      "evidence": "high",
      "method": "Geoarchaeology and palaeo-bay reconstruction",
      "refs": [
        "Garcia Sanjuan et al. 2025"
      ],
      "region": "Andalusia"
    },
    {
      "id": "PAS-qtzarenite",
      "site": "La Pastora tholos, Valencina",
      "site_lat": 37.4095,
      "site_lon": -6.042,
      "source": "Palaeozoic quartzarenite north of Valencina",
      "source_lat": 37.65,
      "source_lon": -5.95,
      "source_precision": "sector-centroid",
      "rock": "Palaeozoic quartzarenite",
      "mass_t": null,
      "km_min": 30,
      "km_max": 35,
      "km_used": 30,
      "mode": "overland / palaeo-estuary",
      "evidence": "high",
      "method": "Petrology versus named outcrops (2024)",
      "refs": [
        "La Pastora provenance 2024"
      ],
      "region": "Andalusia"
    },
    {
      "id": "ALB-pajarete",
      "site": "Alberite I-II",
      "site_lat": 36.847,
      "site_lon": -5.642,
      "source": "Cerro Pajarete / Las Montanas Jurassic limestone",
      "source_lat": 36.78,
      "source_lon": -5.58,
      "source_precision": "named-sector",
      "rock": "Jurassic micritic limestone",
      "mass_t": 8,
      "km_min": 4,
      "km_max": 8.5,
      "km_used": 8,
      "mode": "overland",
      "evidence": "medium",
      "method": "Thin-section match to named hills",
      "refs": [
        "Ramos Munoz 1993"
      ],
      "region": "Andalusia"
    },
    {
      "id": "VDR-barroco",
      "site": "Vale de Rodrigo 1 menhir",
      "site_lat": 38.55,
      "site_lon": -7.98,
      "source": "Alto do Barroco muscovite granite",
      "source_lat": 38.48,
      "source_lon": -7.9,
      "source_precision": "named-outcrop",
      "rock": "Muscovite granite",
      "mass_t": 13.5,
      "km_min": 10,
      "km_max": 10,
      "km_used": 10,
      "mode": "overland",
      "evidence": "high",
      "method": "Mapped granite varieties (Kalb and Hoeck)",
      "refs": [
        "Kalb 1996"
      ],
      "region": "Alentejo"
    },
    {
      "id": "PUI-folg",
      "site": "Dolmen de Puigseslloses",
      "site_lat": 41.9386,
      "site_lon": 2.318,
      "source": "Folgueroles Sandstone Formation",
      "source_lat": 41.922,
      "source_lon": 2.348,
      "source_precision": "named-formation",
      "rock": "Arkose / hybrid sandstone",
      "mass_t": null,
      "km_min": 2.5,
      "km_max": 3.5,
      "km_used": 3,
      "mode": "overland",
      "evidence": "high",
      "method": "Comparative petrography and sedimentology",
      "refs": [
        "Clop et al. 2006"
      ],
      "region": "Catalonia"
    },
    {
      "id": "SH-bluestone-goedog",
      "site": "Stonehenge bluestones",
      "site_lat": 51.17888,
      "site_lon": -1.82622,
      "source": "Carn Goedog spotted dolerite",
      "source_lat": 51.9735,
      "source_lon": -4.726,
      "source_precision": "named-quarry",
      "rock": "Spotted dolerite",
      "mass_t": 3,
      "km_min": 220,
      "km_max": 240,
      "km_used": 230,
      "mode": "sea / coastal then overland",
      "evidence": "high",
      "method": "Petrography, ICP-MS, excavated extraction debris",
      "refs": [
        "Bevins et al. 2020"
      ],
      "region": "Britain"
    },
    {
      "id": "SH-rhyolite-crf",
      "site": "Stonehenge rhyolite / Newall boulder",
      "site_lat": 51.17888,
      "site_lon": -1.82622,
      "source": "Craig Rhos-y-felin foliated rhyolite",
      "source_lat": 51.9919,
      "source_lon": -4.7447,
      "source_precision": "named-quarry",
      "rock": "Foliated rhyolite Groups A-C",
      "mass_t": 2,
      "km_min": 220,
      "km_max": 240,
      "km_used": 230,
      "mode": "sea / coastal then overland",
      "evidence": "high",
      "method": "Petrography, geochemistry, pillar morphology",
      "refs": [
        "Bevins et al. 2020"
      ],
      "region": "Britain"
    },
    {
      "id": "SH-altar",
      "site": "Stonehenge Altar Stone",
      "site_lat": 51.17888,
      "site_lon": -1.82622,
      "source": "Orcadian Basin ORS - Caithness / Inverness-Black Isle sector",
      "source_lat": 58.45,
      "source_lon": -3.2,
      "source_precision": "basin-sector",
      "rock": "Micaceous Old Red Sandstone",
      "mass_t": 6,
      "km_min": 750,
      "km_max": 900,
      "km_used": 750,
      "mode": "sea / east-coast (glacial relay insufficient)",
      "evidence": "high",
      "method": "Detrital zircon U-Pb, rutile, apatite",
      "refs": [
        "Clarke et al. 2024 Nature"
      ],
      "region": "Britain"
    },
    {
      "id": "SH-sarsen",
      "site": "Stonehenge sarsens (50 of 52)",
      "site_lat": 51.17888,
      "site_lon": -1.82622,
      "source": "West Woods, Marlborough Downs",
      "source_lat": 51.392,
      "source_lon": -1.72,
      "source_precision": "named-plateau",
      "rock": "Sarsen (silcrete)",
      "mass_t": 20,
      "km_min": 24,
      "km_max": 26,
      "km_used": 25,
      "mode": "overland via Vale of Pewsey / Avon",
      "evidence": "high",
      "method": "pXRF plus ICP-MS of Stone 58 core",
      "refs": [
        "Nash et al. 2020"
      ],
      "region": "Britain"
    },
    {
      "id": "DA-brimham",
      "site": "Devil's Arrows",
      "site_lat": 54.0928,
      "site_lon": -1.4036,
      "source": "Brimham Rocks Millstone Grit",
      "source_lat": 54.0803,
      "source_lon": -1.6858,
      "source_precision": "named-outcrop",
      "rock": "Millstone Grit",
      "mass_t": 25,
      "km_min": 18,
      "km_max": 18,
      "km_used": 18,
      "mode": "overland",
      "evidence": "high",
      "method": "Zircon-apatite U-Pb; ice-flow mismatch",
      "refs": [
        "Clarke et al. 2026 Proc. R. Soc. A"
      ],
      "region": "Britain"
    },
    {
      "id": "BRO-vestra",
      "site": "Ring of Brodgar / Stones of Stenness",
      "site_lat": 59.0014,
      "site_lon": -3.2297,
      "source": "Vestra Fiold quarry",
      "source_lat": 59.07,
      "source_lon": -3.312,
      "source_precision": "excavated-quarry",
      "rock": "Old Red Sandstone flag",
      "mass_t": null,
      "km_min": 6,
      "km_max": 8,
      "km_used": 7,
      "mode": "overland",
      "evidence": "high",
      "method": "Excavated quarry plus lithology groups",
      "refs": [
        "Richards 2013"
      ],
      "region": "Orkney"
    },
    {
      "id": "NEW-clogher",
      "site": "Newgrange / Knowth kerbstones",
      "site_lat": 53.6947,
      "site_lon": -6.4756,
      "source": "Clogher Head greywacke",
      "source_lat": 53.793,
      "source_lon": -6.218,
      "source_precision": "named-coast",
      "rock": "Greywacke",
      "mass_t": 2,
      "km_min": 20,
      "km_max": 32,
      "km_used": 20,
      "mode": "coastal then river",
      "evidence": "high",
      "method": "Lithology versus coastal greywacke outcrop",
      "refs": [
        "Mitchell 1992",
        "Cooney 2000"
      ],
      "region": "Ireland"
    },
    {
      "id": "NEW-wicklow",
      "site": "Newgrange quartz facade",
      "site_lat": 53.6947,
      "site_lon": -6.4756,
      "source": "Wicklow vein quartz (Glendalough area)",
      "source_lat": 53.0106,
      "source_lon": -6.3275,
      "source_precision": "named-sector",
      "rock": "White vein quartz cobbles",
      "mass_t": null,
      "km_min": 50,
      "km_max": 70,
      "km_used": 60,
      "mode": "overland / coastal",
      "evidence": "high",
      "method": "Isotopic and petrographic match",
      "refs": [
        "Meighan et al. 2003"
      ],
      "region": "Ireland"
    },
    {
      "id": "LHB-foreshore",
      "site": "La Hougue Bie",
      "site_lat": 49.2004,
      "site_lon": -2.0639,
      "source": "Eastern Jersey outcrops and foreshore",
      "source_lat": 49.18,
      "source_lon": -2.02,
      "source_precision": "island-sector",
      "rock": "At least nine island lithologies",
      "mass_t": null,
      "km_min": 2,
      "km_max": 8,
      "km_used": 5,
      "mode": "overland uphill from shore",
      "evidence": "medium",
      "method": "Multi-lithology inventory (Patton)",
      "refs": [
        "Patton 1992"
      ],
      "region": "Channel Islands"
    },
    {
      "id": "LOU-poudingue",
      "site": "Loudunais megaliths",
      "site_lat": 47.0097,
      "site_lon": 0.0811,
      "source": "Polygenic conglomerate outcrops ~12 km",
      "source_lat": 47.09,
      "source_lon": 0.18,
      "source_precision": "sector-centroid",
      "rock": "Polygenic conglomerate (poudingue)",
      "mass_t": null,
      "km_min": 11,
      "km_max": 13,
      "km_used": 12,
      "mode": "overland",
      "evidence": "medium",
      "method": "Mens geological survey of the Loudunais",
      "refs": [
        "Mens 2016",
        "Mens et al. 2022"
      ],
      "region": "West-central France"
    },
    {
      "id": "PER-angoumois",
      "site": "Petite Perotte",
      "site_lat": 45.914,
      "site_lon": 0.168,
      "source": "Callovian / Oxfordian limestone sources 4-7 km",
      "source_lat": 45.96,
      "source_lon": 0.22,
      "source_precision": "sector-centroid",
      "rock": "Jurassic limestone",
      "mass_t": 40,
      "km_min": 4,
      "km_max": 7,
      "km_used": 6,
      "mode": "overland",
      "evidence": "medium",
      "method": "Architectural geology of Angoumois dolmens",
      "refs": [
        "Ard, Mens and Poncet 2016"
      ],
      "region": "West-central France"
    },
    {
      "id": "AUV-pessat",
      "site": "Pessat-Villeneuve menhir (Auvergne set)",
      "site_lat": 45.928,
      "site_lon": 3.159,
      "source": "Western volcanic / plateau source used by Limagne erections",
      "source_lat": 45.93,
      "source_lon": 2.98,
      "source_precision": "sector-centroid",
      "rock": "Basalt and other volcanics",
      "mass_t": 10,
      "km_min": 12,
      "km_max": 15,
      "km_used": 14,
      "mode": "overland inland",
      "evidence": "medium",
      "method": "Petrographic matching (Surmely and Goer de Herve)",
      "refs": [
        "Surmely et al. 1996"
      ],
      "region": "Massif Central"
    },
    {
      "id": "ROU-pierre-plantee",
      "site": "Pierre Plantee / Rouergue statue-menhirs",
      "site_lat": 43.7,
      "site_lon": 2.69,
      "source": "Local granite / sandstone facies 3-18 km",
      "source_lat": 43.71,
      "source_lon": 2.66,
      "source_precision": "sector-centroid",
      "rock": "Granite (this example); group also uses sandstones",
      "mass_t": 9.5,
      "km_min": 3,
      "km_max": 18,
      "km_used": 8,
      "mode": "overland upland",
      "evidence": "medium",
      "method": "Named source facies for individual statues",
      "refs": [
        "Maille 2010"
      ],
      "region": "Massif Central"
    },
    {
      "id": "VIL-mylonite",
      "site": "Dolmen de El Torrejon (Villarmayor)",
      "site_lat": 41.154,
      "site_lon": -5.706,
      "source": "Juzbado-Traguntia shear-zone mylonite / two-mica granite",
      "source_lat": 41.178,
      "source_lon": -5.735,
      "source_precision": "sector-centroid",
      "rock": "Mylonitised granite and two-mica granite",
      "mass_t": 2.4,
      "km_min": 3.0,
      "km_max": 4.2,
      "km_used": 3.6,
      "mode": "overland",
      "evidence": "medium",
      "method": "Field petrography matched to mapped units; minimum haul per orthostat",
      "refs": [
        "Lopez Plaza, Lopez Plaza and Lopez Moro 2008"
      ],
      "region": "Northern Meseta"
    },
    {
      "id": "TOR-leucogranite",
      "site": "Dolmen de Torrecilla (statue-menhir)",
      "site_lat": 40.985,
      "site_lon": -5.78,
      "source": "Tourmaline leucogranite band (southern granite)",
      "source_lat": 40.92,
      "source_lon": -5.85,
      "source_precision": "sector-centroid",
      "rock": "Tourmaline leucogranite",
      "mass_t": null,
      "km_min": 9.5,
      "km_max": 9.5,
      "km_used": 9.5,
      "mode": "overland",
      "evidence": "medium",
      "method": "Lithology unique in the tomb; nearest matching leucogranite 9.5 km",
      "refs": [
        "Lopez Plaza, Lopez Plaza and Lopez Moro 2008"
      ],
      "region": "Northern Meseta"
    },
    {
      "id": "KER-porzmeur",
      "site": "Allee couverte de Kernic (Guinirvit)",
      "site_lat": 48.65682,
      "site_lon": -4.21596,
      "source": "Porz Meur / Plouescat granite outcrops (three sites)",
      "source_lat": 48.661,
      "source_lon": -4.207,
      "source_precision": "named-outcrop",
      "rock": "Plouescat granite (three facies)",
      "mass_t": 4,
      "km_min": 0.7,
      "km_max": 1.0,
      "km_used": 1.0,
      "mode": "overland / foreshore",
      "evidence": "high",
      "method": "Petro-structural match of jointed granite facies to three mapped outcrops",
      "refs": [
        "Gorczynska, Le Gall, Stephan and Pailler 2023"
      ],
      "region": "Brittany"
    },
    {
      "id": "SOT-allochthon",
      "site": "Dolmen de Soto (allochthonous suite)",
      "site_lat": 37.35222,
      "site_lon": -6.75139,
      "source": "Niebla calcarenite / western Sierra Morena igneous-sedimentary suite",
      "source_lat": 37.36,
      "source_lon": -6.55,
      "source_precision": "sector-centroid",
      "rock": "Calcarenite, sandstone, dacite (not greywacke)",
      "mass_t": null,
      "km_min": 20,
      "km_max": 60,
      "km_used": 30,
      "mode": "overland / palaeo-estuary",
      "evidence": "medium",
      "method": "Geoarchaeology of minority lithologies (Linares-Catela); 100 km Gerena granite omitted pending stone-by-stone tables",
      "refs": [
        "Linares Catela and Mora Molina 2018",
        "Linares-Catela 2023"
      ],
      "region": "Andalusia"
    },
    {
      "id": "GG-poudingue",
      "site": "Pierre Levee du Grand Gat",
      "site_lat": 46.8665,
      "site_lon": -0.4485,
      "source": "Siliceous conglomerate (poudingue) outcrops ~10-11 km",
      "source_lat": 46.9,
      "source_lon": -0.33,
      "source_precision": "sector-centroid",
      "rock": "Siliceous conglomerate (capstone); chamber also Noirlieu granodiorite + Thouars microgranite <=3 km",
      "mass_t": null,
      "km_min": 10,
      "km_max": 11,
      "km_used": 10.5,
      "mode": "overland",
      "evidence": "high",
      "method": "Petrography of orthostats and capstone; mapped granitoid (<=3 km) and poudingue (10-11 km) sources (Poncet and Mens 2023). Capstone row uses the longer haul; source centroid approximate pending figure digitisation.",
      "refs": [
        "Poncet and Mens 2023"
      ],
      "region": "West-central France"
    },
    {
      "id": "PAS-granite",
      "site": "La Pastora tholos, Valencina (granite)",
      "site_lat": 37.4095,
      "site_lon": -6.042,
      "source": "Guillena-Gerena batholith (Sierra Norte de Sevilla)",
      "source_lat": 37.52,
      "source_lon": -6.05,
      "source_precision": "named-sector",
      "rock": "Jointed epizonal granite",
      "mass_t": null,
      "km_min": 14,
      "km_max": 16,
      "km_used": 15,
      "mode": "overland",
      "evidence": "high",
      "method": "Petrography and jointed-batholith match; distinct from PAS-qtzarenite quartzarenite haul",
      "refs": [
        "Caceres et al. 2024 Minerals 14(2):194"
      ],
      "region": "Andalusia"
    },
    {
      "id": "MON-gerena",
      "site": "Montelirio tholos corridor, Valencina",
      "site_lat": 37.415,
      "site_lon": -6.035,
      "source": "Gerena-Aznalcollar Paleozoic granite and grey/green shale",
      "source_lat": 37.53,
      "source_lon": -6.1,
      "source_precision": "named-sector",
      "rock": "Granite and shale (42 corridor capstones; sandstone from Aljarafe shorter)",
      "mass_t": null,
      "km_min": 15,
      "km_max": 20,
      "km_used": 17,
      "mode": "overland",
      "evidence": "high",
      "method": "Petrography of 42 corridor capstones (Montelirio monograph): granite/shale from Gerena-Aznalcollar Paleozoic; km_used ~17 is an envelope aligned with the nearby Pastora granite ~15 km batholith match, not a stone-by-stone measured path.",
      "refs": [
        "Fernandez Flores et al. Montelirio monograph"
      ],
      "region": "Andalusia"
    },
    {
      "id": "RAB-capstone",
      "site": "Anta de Rabuje 1",
      "site_lat": 39.05,
      "site_lon": -7.38,
      "source": "Compatible non-local outcrop (not nearby stratum)",
      "source_lat": 39.08,
      "source_lon": -7.3,
      "source_precision": "sector-centroid",
      "rock": "Granitoid / slab not matching adjacent bedrock",
      "mass_t": null,
      "km_min": 6,
      "km_max": 8,
      "km_used": 8,
      "mode": "overland",
      "evidence": "medium",
      "method": "Field petrography and whole-rock geochemistry vs local stratum (Boaventura); longer haul when local rock unsuitable. Source point is a sector centroid — tighten from the paper figures before treating as a pegged quarry.",
      "refs": [
        "Boaventura 2000",
        "Boaventura and Moita 2012"
      ],
      "region": "Alentejo"
    },
    {
      "id": "AIZ-quartzarenite",
      "site": "Aizkomendi dolmen (Eguilaz)",
      "site_lat": 42.861,
      "site_lon": -2.275,
      "source": "Albian quartzarenite, Urkilla / Aizkorri sector",
      "source_lat": 42.9,
      "source_lon": -2.33,
      "source_precision": "named-sector",
      "rock": "Albian quartzarenite (also Paleocene limestone >=3 km from Entzia-Iturrieta)",
      "mass_t": 4.5,
      "km_min": 5,
      "km_max": 8,
      "km_used": 5,
      "mode": "overland",
      "evidence": "high",
      "method": "Geoarchaeology of Rioja Alavesa dolmens; named formation matches",
      "refs": [
        "Martinez-Torres et al. 2017",
        "Vegas et al. 1992"
      ],
      "region": "Northern Iberia"
    },
    {
      "id": "VIL-montipranu",
      "site": "Villaperuccio menhirs (Terrazzu / Is Pireddas)",
      "site_lat": 39.072,
      "site_lon": 8.675,
      "source": "Monti Pranu-Tratalias ignimbrite quarry",
      "source_lat": 39.1,
      "source_lon": 8.6,
      "source_precision": "named-quarry",
      "rock": "Ignimbrite",
      "mass_t": null,
      "km_min": 7.0,
      "km_max": 8.6,
      "km_used": 8.0,
      "mode": "overland",
      "evidence": "medium",
      "method": "Quarry traces plus macroscopic ignimbrite match (Serra ArcheoArte); distances 7-8.6 km from Monti Pranu-Tratalias. Medium grade; source/site coords are approximate sector/group pins.",
      "refs": [
        "Serra 2015-2021 ArcheoArte"
      ],
      "region": "Sardinia"
    },
    {
      "id": "NEW-mourne",
      "site": "Newgrange granite facade cobbles",
      "site_lat": 53.6947,
      "site_lon": -6.4756,
      "source": "Mourne / Newry granite",
      "source_lat": 54.15,
      "source_lon": -6.05,
      "source_precision": "named-sector",
      "rock": "Granite cobbles",
      "mass_t": null,
      "km_min": 45,
      "km_max": 55,
      "km_used": 50,
      "mode": "overland / coastal",
      "evidence": "medium",
      "method": "Medium: facade granite cobbles attributed to Mourne/Newry suite in published Newgrange lithology reviews; distinct from Wicklow quartz (NEW-wicklow). Sector centroid approximate.",
      "refs": [
        "Mitchell 1992",
        "Meighan et al. 2003"
      ],
      "region": "Ireland"
    },
    {
      "id": "BRO-houton",
      "site": "Ring of Brodgar (yellow sandstone)",
      "site_lat": 59.0014,
      "site_lon": -3.2297,
      "source": "Houton (Orphir) Eday Group sandstone",
      "source_lat": 58.93,
      "source_lon": -3.18,
      "source_precision": "named-sector",
      "rock": "Yellow Old Red Sandstone",
      "mass_t": null,
      "km_min": 12,
      "km_max": 15,
      "km_used": 14,
      "mode": "overland",
      "evidence": "medium",
      "method": "Medium: multi-quarry Brodgar lithology groups include yellow Eday sandstone linked to Houton (Orphir) in Richards 2013 synthesis; distinct from Vestra Fiold (BRO-vestra). Sector centroid approximate.",
      "refs": [
        "Richards 2013"
      ],
      "region": "Orkney"
    },
    {
      "id": "MAE-staneyhill",
      "site": "Maeshowe",
      "site_lat": 58.9981,
      "site_lon": -3.1883,
      "source": "Staneyhill excavated quarry",
      "source_lat": 59.015,
      "source_lon": -3.17,
      "source_precision": "excavated-quarry",
      "rock": "Old Red Sandstone flag",
      "mass_t": null,
      "km_min": 2.5,
      "km_max": 3.5,
      "km_used": 3,
      "mode": "overland",
      "evidence": "high",
      "method": "Excavated quarry linked to Maeshowe construction",
      "refs": [
        "Richards et al. 2013"
      ],
      "region": "Orkney"
    },
    {
      "id": "FRE-redondo",
      "site": "Freixo-Redondo dolmens (group envelope)",
      "site_lat": 38.62,
      "site_lon": -7.78,
      "source": "Petrographically matched outcrops (not nearest exposures)",
      "source_lat": 38.635,
      "source_lon": -7.76,
      "source_precision": "sector-centroid",
      "rock": "Granodiorite and related",
      "mass_t": null,
      "km_min": 0.8,
      "km_max": 3.5,
      "km_used": 2.0,
      "mode": "overland",
      "evidence": "high",
      "method": "Microscopy and whole-rock geochemistry; selective sourcing within 0.8-3.5 km (not nearest outcrop). One row for the Freixo group envelope — not a single monument pin; split if stone-by-stone tables are needed.",
      "refs": [
        "Boaventura et al. 2020 Megaliths and Geology"
      ],
      "region": "Alentejo"
    },
    {
      "id": "TDM-sabals",
      "site": "Table des Marchands (gres a sabals slab)",
      "site_lat": 47.5717,
      "site_lon": -2.9495,
      "source": "East Golfe du Morbihan sabal sandstone outcrops",
      "source_lat": 47.55,
      "source_lon": -2.82,
      "source_precision": "sector-centroid",
      "rock": "Gres a sabals / gres ladere",
      "mass_t": null,
      "km_min": 10,
      "km_max": 15,
      "km_used": 10,
      "mode": "overland / coastal",
      "evidence": "medium",
      "method": "QUARANTINE pending primary petro paper: architectural-geology synthesis attributes a Locmariaquer chamber end-slab to Morbihan sabal sandstone facies at >=10 km. Distinct from GMB/GAV orthogneiss; not yet re-run with modern thin-section/ICP. Do not treat as high-grade until cited primary work is confirmed.",
      "refs": [
        "Le Roux Locmariaquer geology",
        "L Helgouach synthesis"
      ],
      "region": "Brittany"
    },
    {
      "id": "WM-cerrig",
      "site": "Waun Mawn circle",
      "site_lat": 51.972,
      "site_lon": -4.791,
      "source": "Cerrig Lladron unspotted dolerite",
      "source_lat": 51.965,
      "source_lon": -4.765,
      "source_precision": "named-outcrop",
      "rock": "Unspotted dolerite",
      "mass_t": null,
      "km_min": 2.2,
      "km_max": 2.6,
      "km_used": 2.4,
      "mode": "overland",
      "evidence": "high",
      "method": "Petrography/geochemistry; Preseli local control - not a Stonehenge bluestone haul",
      "refs": [
        "Pearce / Bevins et al. 2022 JAS Reports"
      ],
      "region": "Britain"
    }
  ]
}