Skylab was the first American space station. It was launched in one piece on May 14, 1973.
The station was about three times larger than Salyut and was actually a rebuilt 3rd stage from the Saturn 5 rocket, which was used to launch the Apollo spacecraft to the Moon. It was visited by a total of nine astronauts, who were launched with three spaceships, using a command module from the Apollo program. Skylab crashed over Australia and the Indian Ocean on July 11, 1979.
Space travel related to Skylab
In addition, there was a planned spaceflight:
SKYLAB: A CHRONOLOGY by Roland W. Newkirk and Ivan D. Ertel with Courtney G. Brooks (NASA SP-4011 1977)
SP-402 A New Sun: The Solar Results from Skylab
Skylab Mission Evaluation - NASA report (PDF format)
Skylab Reactivation Mission Report 1980 - NASA report (PDF format)
Skylab Our First Space Station - NASA report (PDF format)
Skylab Restoration Project
Skylab Orbit Video of Skylab orbitting Earth as Skylab Mission 2 approaches it