Continuity mistake: After Cyborg switches the microphones back on and Raven asks whether he could 'accidentally' leave it off, Beast Boy swells his vein. In that shot you can see the yellow marking stripe from the Titan Tower's sub hangar outside BB's canopy, however, at this time they are already in the deep sea. It's simply a repetition of an earlier scene.
Continuity mistake: When Beast Boy and Aqualad each spot one of the Trident clones in the volcanic cave, they look away from each other, but when they try to point him out to the other, shouting "There he goes!", they are pointing over to the direction opposite the one each of them was just facing.
Chosen answer: It is located in California, as shown in "Teen Titans: Trouble in Tokyo". Possibly San Francisco as seen in the comics.
MasterOfAll