Underground — may refer to:* Underground rapid transit system, urban railway ** London Underground, a metro system that covers the Greater London area * Resistance movement, an opposition to an invader, a political position, or to a government * Underground… … Wikipedia
Underground 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… … Wikipedia
Underground Atlanta — is a shopping and entertainment district in the Five Points neighborhood of downtown Atlanta, Georgia, United States, near the intersection of the MARTA rail lines. First opened in 1969, it takes advantage of the viaducts built over the city s… … Wikipedia
Underground mining (soft rock) — refers to a group of underground mining techniques used to extract coal, oil shale and other minerals or geological materials from sedimentary ( soft ) rocks. Because deposits in sedimentary rocks are commonly layered and relatively less hard,… … Wikipedia
Underground Electric Railways Company of London — Geographic map of the UERL s three deep level tube lines in 1907 Part of a series of article … Wikipedia
Underground economy — The underground economy or black market is a market consisting of all commerce on which applicable taxes and/or regulations of trade are being avoided. The term is also often known as the underdog, shadow economy, black economy or parallel… … Wikipedia
Underground Electric Railways Company — The Underground Electric Railways Company of London Limited (UERL) was the holding company for three of the new deep level tube underground railway lines constructed in London in the first decade of the 20th century. It was established in 1902 by … Wikipedia
Underground Railroad — This article is about the 19th century slave escape routes. For an article about railroads built below ground, see rapid transit. For the band, see Underground Railroad (band). Part of a series on … Wikipedia
Underground press — The phrase underground press is most often used to refer to the independently published and distributed underground papers associated with the counterculture of the late 1960s and early 1970s. It also refers to illegal publications under… … Wikipedia
Underground nuclear testing — Preparation for an underground nuclear test at the Nevada Test Site in the 1990s. Nuclear weapons … Wikipedia
