With light industry, warehouses and some office space, 55 businesses are located in SubTropolis. With its sheer size, the underground area also has its own transit infrastructure. Beyond the novelty, though, this underground space could offer a model for future environmentally-conscious development.
"With 5 million square feet of leased warehouse, light-industry, and office space, and a network of more than two miles of rail lines and six miles of roads, SubTropolis is the world's largest underground business complex-and one of eight or so in the area. To people along this stretch of the Missouri River, however, subterranean development also represents an innovative local way to save energy and reduce greenhouse-gas emissions."