The Excelsior-class was a type of Federation starship used by Starfleet from the late 23rd century through the late 24th century. It was the backbone of Starfleet for nearly a century, making it one of the longest serving starship designs, and one of the most recognizable ships in the fleet.
The Excelsior-class was initially constructed during the early 2280s at Starfleet's San Francisco Fleet Yards orbiting Earth.
Starfleet had high hopes for the first ship of this class, the prototype USS Excelsior, which was equipped with a transwarp drive, and was regarded as that century's "Great Experiment."
Despite the failure of the "Great Experiment," Starfleet forged ahead with employing the Excelsior design. After remaining in the Earth Spacedock until at least 2287, the prototype Excelsior was subsequently recommissioned for active service by 2290.