On April 23, 1971 Soyuz 10 was launched as the first Soviet space station. The astronauts docked the station but couldn't enter there for it was not successful.
Although Soyuz 10 failed, the Soviet Union bounced back with Salyut 1 on June 6. Astronauts Dobrovolsky, Volkov, and Patsayev became the first crew of the Salyut 1 space station.
They were in orbit for 24 days, doing experiments, observations, and other tasks. The mission ended after all three astronauts were killed by a sudden cabin leak prior to their return to Earth.