Mir was a Soviet/Russian space station, and was the first modular space station. It operated from 1986 to 2001, at which time it was deorbited. During its lifespan in was the largest human-made object in orbit, consisting of seven pressurized modules and assorted attachments. The station orbited between 296 km (184 mi) and 421 km (262 mi), placing it in low Earth orbit.
Salyut program -- Mir -- International Space Station