A free online service can tell pupils whether they live on top of an extinct volcano or on the bed of an ancient sea once teeming with exotic creatures.
OpenGeoscience, set up by the British Geological Survey, provides maps for the whole of Great Britain, images from a collection of 50,000 photographs and a wide range of other information.
The maps, for example, show that Glasgow is built on the remains of a tropical forest and that Edinburgh is on an extinct volcano. Photographs include images of recent floods in Britain, erupting volcanoes and 1930s cave exploration.
The society has been making geological maps for 175 years, but this is first time such detailed information has become widely available on the internet.
Steve Drury, senior lecturer in remote sensing at the Open University, said the level of detail provided by the service marked a world first: "It will become a kind of `GoogleRock' for a great many people."