The submarine pen appears to serve as storage and shelter for equipment and boats. It consists of three entrances, the north-most of which may serve as a spawn point for the Launch. Several exterior docking points around the base also serve as spawn locations for the Reefer.
A large courtyard at the southern quarter of the base as it merges with the main road creates a triangular section where a Hunter may spawn after all-Gold completions of Flight School. Behind the main base, a Barracks can spawn, and a military-styled Patriot can spawn near the LHD.
Like Area 69, Easter Basin Naval Station is a restricted area. The player will be granted a 5 star wanted level upon entry, be it on-foot, inside any type of vehicle, or flying low above the site. The LHD features surface-to-air missiles, however these are only used during the mission, and are disabled outside of this mission.
The base has defined ped paths, allowing police officers to spawn in the base when the player is wanted. Military officers will not spawn, as they are not able to spawn on foot in paths. On rare occurrences, civilian pedestrians, including prostitutes, may walk into the base from nearby streets.
Easter Basin Naval Station appears to be based on the former Hunter's Point Naval Shipyard in San Francisco.
Events of Grand Theft Auto: San Andreas
In the mission Vertical Bird, Mike Toreno comes to protagonist Carl "CJ" Johnson one last time for a job. CJ is to invade the LHD and steal a Hydra. Then, after having outfought three pursuing Hydras, CJ destroys several spy ships in the Sherman Reservoir. After completing his tasks, Carl parks the jet in a hangar at the Verdant Meadows airfield.
- One snapshot - above the mounted SAM site. This can be safely taken from distance from a boat.
- Two oysters. These oysters are the most difficult to obtain because the player will instantly get a 5-star wanted level when trespassing within the base's perimeter, though sometimes it will drop to 4 stars if fleeing the base by boat:
- One in front of the LHD
- One in the middle tunnel of the sub pen
It is best to collect these oysters during Vertical Bird before reaching the back of the LHD, as the wanted level is deactivated for the mission. The mission The Da Nang Thang also allows exploration right after the helicopter was taken down. If not, it is recommended to use a speedboat for a quick getaway then escape east, go upstream and save at Mike Toreno's Ranch or the Fort Carson Safehouse. Alternatively, park the boat near the NRG-500 in the docks area and make a run for the Doherty Safehouse with the NRG-500 via the railway line. This will fail the repeatable NRG-500 Challenge but the upside is that the cops near the player despawn when the challenge starts.
- A helipad appears marked on the map, despite not being present.