it is two metres underground
1Underground city — An underground city is a network of tunnels that connect buildings beneath street level. These may include office blocks, shopping malls, train and metro stations, theatres, and other attractions. An underground city can usually be accessed… …
2Underground coal gasification — (UCG) is an in situ gasification process carried out in non mined coal seams using injection and production wells drilled from the surface, which enables the coal to be converted into product gas. The process is flexible in operation and is… …
3Underground nuclear testing — Preparation for an underground nuclear test at the Nevada Test Site in the 1990s. Nuclear weapons …
4Underground mining (hard rock) — A three dimensional model of an underground mine with shaft access Underground hard rock mining refers to various underground mining techniques used to excavate hard minerals, mainly those containing metals[1] such as ore containing gold …
5Underground home — An underground home is a house or dwelling which lies either under the standard ground level on a flat piece of land, or built into a hillside or mountain side. HistoryThere is only written documentation of Scythian and German subterranean… …
6Meuse/Haute Marne Underground Research Laboratory — The Meuse/Haute Marne Underground Research Laboratory is a laboratory located 500 metres underground in Bure in the Meuse département. It allows to study the geological formation in order to evaluate its capacity for deep geological repository of …
7tunnels and underground excavations — ▪ engineering Introduction Great tunnels of the world Great tunnels of the worldhorizontal underground passageway produced by excavation or occasionally by nature s action in dissolving a soluble rock, such as limestone. A vertical opening …
8London Underground infrastructure — The infrastructure of the London Underground includes 11 lines, which serve 268 stations by rail. Lines on the Underground can be classified into two types: subsurface and deep level. Lines of both types usually emerge onto the surface outside… …
9Circle line (London Underground) — Circle Colour on map Yellow Year opened 1884 Line type Sub Surface Rolling stock C Stock 6 carriages per trainset …
10History of the London Underground — The history of the London Underground is one of gradual evolution. One section of it was the first urban underground passenger carrying railway in the world, for although the Atlantic Avenue Tunnel in New York, opened in 1844, is sometimes called …
