What's beneath your feet?
Type an address or share your location and fly down into the ground under it: the rock the surveys have mapped, the drill holes, old workings and mining licences around you, then on through the crust to the centre of the Earth.
Your location stays in your browser. We never store it.
What the page shows
Pick a place and the page cuts a block out of the ground beneath it, 1, 3 or 10 kilometres across, with the satellite picture and the real shape of the land on top. The walls of the block are painted with the rock the geological surveys have mapped there, layer by layer. Where a stratigraphic column exists (most of North America and some other regions) each layer has its measured thickness and age; elsewhere you see the surface rock and the bedrock below it, drawn to a typical thickness and labelled as such.
Into the block go the drill holes. We hold 3.8 million open-file holes that the governments of Western Australia, South Australia, New South Wales, the Northern Territory, Victoria, Tasmania, Québec, Finland, Sweden and Saskatchewan publish. Each hole is drawn at its true angle and depth, coloured by its best assay for the metal you choose. Pins mark 501,000 old workings, mines, deposits and mineral occurrences from Geoscience Australia and the USGS, and outlines show 912,000 mining and exploration licences from the open registers. Dive takes you down the layers one by one; To the core keeps going, through the crust and the mantle to the centre of the Earth, with the deepest hole at your spot and the deepest hole ever drilled marked on the way.
Places to try
- Kalgoorlie Super Pit the Golden Mile, the most drilled square kilometres in Australia
- Broken Hill the line of lode under a city
- Olympic Dam a copper giant found under 300 m of cover
- Ballarat the deep leads of the 1850s gold rush
- Tennant Creek ironstone gold in the Northern Territory
- Queenstown, Tasmania Mount Lyell copper on the west coast
- Perth city centre a capital on sand: what is under a city with no mine
- Adelaide the city that copper built
- Val-d'Or, Québec the Abitibi gold belt
- Kiruna, Sweden the iron-ore town that is moving
- McArthur River, Saskatchewan uranium under the Athabasca Basin
- Outokumpu, Finland Finland's copper story
- Denver, Colorado a full layer cake of rocks, 48 units deep
- Butte, Montana the richest hill on Earth
- Camborne, Cornwall tin and copper country
- Sudbury, Ontario nickel in a meteorite crater
Questions people ask
What is under my house?
Under almost every house is a thin skin of soil and loose sediment, then bedrock that can be hundreds of millions or billions of years old. Type your address above and the page shows the rock the geological survey has mapped at that spot, the layers beneath it where a stratigraphic column exists, and any drill holes, old mines or licences nearby.
How deep do drill holes go?
Most exploration holes are 50 to 300 metres deep: shallow aircore and RAB holes test the weathered rock, and diamond holes chase ore below 1,000 metres. The deepest hole ever drilled, the Kola Superdeep Borehole in Russia, reached 12,262 metres, about a third of the way through the continental crust.
Is my location stored?
No. When you share your location it stays in your browser. The page sends the point (rounded to about 100 metres) straight from your browser to Macrostrat for the rock, to Esri for the satellite picture and to the terrain service for the ground shape; our servers never see it unless you copy a share link yourself.
Where does the geology come from?
From Macrostrat, a free database run by the University of Wisconsin-Madison that brings together geological maps from national surveys and, across North America, stratigraphic columns that list each layer with its thickness and age. Outside the columns we show the mapped surface rock and the bedrock from the broader-scale maps, and say so when a layer is drawn to a typical rather than a measured thickness.
Why are there so many drill holes in some places and none in others?
We hold the open-file drill holes that governments publish: Western Australia, South Australia, New South Wales, the Northern Territory, Victoria, Tasmania, Québec, Finland, Sweden and Saskatchewan. Elsewhere companies still drill, but their holes are not in an open database we can republish, so the page shows the rock, the old workings and the licences instead.
How to read it
The block is drawn at true scale: one metre across is one metre down, and the land is not stretched. Drill holes come from company reports lodged with each government and are shown as they were reported: they belong to the explorers who drilled them, often decades ago, not to whoever holds the ground today. Grades are each hole's best single assay, not an intersection or a resource, and some reported values contain unit errors. Where a source gives no angle, a hole is drawn straight down and the card says so. Licences are a snapshot of each register and change every week; check the register before relying on one. Geological maps are generalised, so the boundary between two rocks can be tens of metres off at street scale. Nothing here is advice on a property or an investment.
Sources
- Drill holes, WAMEX open-file drill holes, Western Australia (CC BY 4.0): Based on Department of Mines, Petroleum and Exploration (Western Australia) material, CC BY 4.0. The map of every hole.
- Drill holes, SARIG data package: drillholes and rock sample geochemistry (SA Geodata extract) (CC BY 4.0): Based on data from The Department for Energy and Mining, the Government of South Australia, SARIG data package, Sourced on 24 October 2026, https://dem-sdp.s3-ap-southeast-2.amazonaws.com/index.html, licensed under CC BY 4.0. Filtered, unit-harmonised and desurveyed by Prospector Trails; not endorsed by the Government of South Australia. The map of every hole.
- Drill holes, NSW drillholes (minerals) and drilling geochemistry assays (hole summaries) (CC BY 4.0): Based on Geological Survey of New South Wales data (© State of New South Wales, CC BY 4.0), cleaned and summarised by Prospector Trails. The map of every hole.
- Drill holes, Northern Territory open-file drillhole collars and drillhole maximum assays (NTGS geochemical database) (CC BY 4.0): Based on Northern Territory of Australia (Northern Territory Geological Survey) material, licensed under CC BY 4.0 The map of every hole.
- Drill holes, Borehole Geology and Boreholes (from Earth Resources database) (CC BY 4.0): Based on Earth Resources borehole data © State of Victoria (Department of Energy, Environment and Climate Action), CC BY 4.0, cleaned and summarised by Prospector Trails. The map of every hole.
- Drill holes, Borehole Points Data (Mineral Resources Tasmania) (CC BY 3.0 AU): Based on Mineral Resources Tasmania borehole data (© State of Tasmania, CC BY 3.0 AU), cleaned by Prospector Trails. The map of every hole.
- Drill holes, SIGÉOM diamond drill holes (Forages au diamant) with mineralised intercepts, plus drill-core rock samples from SIGÉOM geochemistry (CC BY 4.0): Contains information from the datasets « Sondages » and « Géochimie » (SIGÉOM) published by the Ministère des Ressources naturelles et des Forêts du Québec (Géologie Québec) on Données Québec (https://www.donneesquebec.ca/recherche/dataset/sondages, https://www.donneesquebec.ca/recherche/dataset/geochimie), updated 10 June 2026 and 8 October 2025, consulted 24 October 2026, under CC BY 4.0. Grades were converted to ppm, cleaned and positioned downhole by Prospector Trails; the Ministère does not endorse this use. The map of every hole.
- Drill holes, Bedrock drill holes of Finland and Sweden (GTK: GTK Open Licence, Creative Commons Attribution 4.0 International): Contains data from the Geological Survey of Finland (GTK), GTK Open License CC Attribution 4.0 (Kallioperäkairaukset and Mineral deposits, accessed 24 October 2026, https://gtkdata.gtk.fi/), edited: reprojected, cleaned and given a target commodity from the nearest known deposit. Contains data from the Geological Survey of Sweden (SGU), CC0 1.0. The map of every hole.
- Drill holes, Minerals and Quaternary Drillhole Compilation (Government of Saskatchewan Standard Unrestricted Use Data Licence): Contains information licensed under the Government of Saskatchewan Standard Unrestricted Use Data Licence (Version 2.0) (https://gisappl.saskatchewan.ca/Html5Ext/Resources/GOS_Standard_Unrestricted_Use_Data_Licence_v2.0.pdf). Data: Saskatchewan Geological Survey drillhole compilation and Mineral Deposit Index, cleaned and given a target commodity by prospectortrails.com. No endorsement by the Government of Saskatchewan is implied. The map of every hole.
- Australian mineral occurrences (Geoscience Australia) (CC BY 4.0): © Commonwealth of Australia (Geoscience Australia), CC BY 4.0. Mineral occurrences, Australian Mines Atlas.
- Australian mineral deposits (Geoscience Australia) (CC BY 4.0): © Commonwealth of Australia (Geoscience Australia), CC BY 4.0. Mineral deposits, Australian Mines Atlas.
- Mineral Resources Data System (USGS) (Public domain): U.S. Geological Survey, Mineral Resources Data System (MRDS), 2011 (data last updated 2022). Public domain.
- Mining and exploration licences from the open registers of New South Wales, Northern Territory, Queensland, South Australia, Tasmania, Victoria, Western Australia, Alberta, British Columbia, New Brunswick, Nova Scotia, Nunavut, Yukon, Republic of the Congo, Cameroon, Spain, France, Great Britain, Greenland, Norway, New Zealand, Sweden, United States (federal, BLM), each under its own open licence, as downloaded on 22 October 2026; the source and its attribution show beside every licence you open.
- Rocks: Macrostrat (CC BY 4.0), which brings together geological maps from national surveys (Geoscience Australia's 1:1 million surface geology for Australia, the USGS state maps, and many more) and the stratigraphic columns of North America; the map behind each answer is named on it.
- Ground shape: Terrain Tiles on AWS Open Data (Mapzen, from SRTM, GMTED, ETOPO1 and national elevation models). Satellite picture: Esri World Imagery, streamed live and never stored (Powered by Esri; Esri, Vantor, Earthstar Geographics). Place search: Photon by komoot, data © OpenStreetMap contributors (ODbL).
More: Under Western Australia, the map of every open-file hole in the state; what exploration drilling is; how prospectors changed the world; and the mining glossary.
Keep exploring
Stories under the ground




All mining storiesThe world runs on rockAll mineralsMining by country
Cover photos from Wikimedia Commons: Super Pit, Kalgoorlie by Kgbo, CC BY-SA 4.0. Pictures: Kimberley, South Africa: miners and washing gear at the Bultfontein diamond mine. Woodburytype, 1888, after a photograph by Robert Harris., Harris, Robert, active 1881-1888. (Public Domain Mark 1.0).