The huge mushroom-shaped starbase in Earth orbit introduced in Star Trek III, home port of the Enterprise in the films and the centre of the Frontier Day attack in 2401.
Earth Spacedock is an enormous station in orbit of Earth, large enough for starships to enter through bay doors and berth inside. It first appears in Star Trek III: The Search for Spock, when the damaged Enterprise returns home and Kirk later steals it from its berth while Scotty sabotages the Excelsior.
The station is seen again in Star Trek IV, V and VI, and stations of the same design appear as other starbases in The Next Generation.
Spacedock returns in the third season of Picard. In the episodes Vox and The Last Generation the fleet gathered for Frontier Day falls under Borg control and turns its weapons on the station, which holds out as Earth's last defence while the rebuilt Enterprise-D destroys the cube directing the attack.