California Base is a massive Earth Federation Forces naval installation composed of 20 large bases on the Californian coast, made up of more than a dozen different naval, aerospace, and weapons development facilities. The California Base was home to the Federation's largest naval yards. During the Principality of Zeon's Earth invasion it is captured on March 13, U.C. 0079 during Zeon's second Earth drop operation, and becomes the Principality's major terrestrial base. After the Zeon captured it during the One Year War the facility was retooled to produce Zeon submarines. After Operation Odessa, the turning point of the war on Earth, the remaining Zeon forces expended much of the bases fighting strength in a failed assault on Jaburo. The California base was recaptured by the Federation during the last month of the war. The story of The Blue Destiny takes part in the recapture of the California base on December 15, U.C. 0079. It ends with the destruction of the experimental EXAM suits, the Blue Destiny unit-1, piloted by Yuu Kajima, and the MS-08TX(EXAM) Efreet Custom, piloted by Zeon Ace Nimbus Schterzen. This battle also lead to the truth about the EXAM system. The base's assembly lines were used to produce at least 500 RGM-79 GM units in the last month of the war.
At California Base, Lt. Agar piloting RX-78-6 Mudrock Gundam saw its service, and in an attempt to prevent the Midnight Fenrir Corp from using an HLV to leave Earth near the end of the One Year War - that battle left the RX-78-6 severely damaged, and the Federation determined that it was not feasible to repair the unit.