"underground crossing" is a correct and usable phrase in written English.
It can refer to a passage or tunnel beneath the ground that is used to cross from one side to the other. Example sentence: The city plans to build an underground crossing beneath the busy street to improve safety for pedestrians.
The Weather Underground crossed lines of legality, of propriety and perhaps even of common sense.
Israel later sent in ground troops to destroy Hamas' underground cross-border tunnels.
Park said underground cross-border trade between China and North Korea has gotten more difficult under Kim's rule.
OF COURSE, the official (if often disheveled) face of retro right now is Amy Winehouse, whose Motown-flavored costume dramas seduced the indie-pop underground before crossing into the Top 10.
Underground utilities crossing the site (oil pipelines, etc). may render otherwise good sites unsuitable for a project.
Call a local locator service if you are not absolutely certain that there are no underground utilities crossing your proposed fence line(s) or if you do not know their location(s).
The line-up, revealed today in the Guardian, spans rock groups from the established to the underground, and crosses artistic boundaries.
B3 Comforts of Home, Delivered Week after week, packages make their way from Puebla, Mexico, to Tulcingo Travel in Jackson Heights, part of a thriving underground of cross-border couriers who fly back and forth between the New York area and Latin America, transporting the sorely-missed pleasures of home to the city's immigrants.
Architects and urban planners who have analysed the city in recent years claim it would probably have been nightmarish to live in: hostile to pedestrians, who would regularly have be sent underground to cross streets, and with a chaotic road system, as Speer's did not believe in traffic lights or trams.
