Ключевые слова: abandoned, architecture, cable, cable tunnel, communication, connection, construction, corridor, dark, deep, drainage, emergency, empty, engineering, evacuation, grunge, heating duct, indoor, indoors, industrial, industry, inside, interior, line, long, maintenance, metro, network, no people, nobody, old, passage, perspective, pipeline, pipelines, railway, rescue, service, subway, technical, transport, transportation, tube, tunnel, under, underground, underground communication, urban, wall, wires,