Continuity mistake: When Beast Boy and Gizmo flee from the white blood cell tide and pass through the gunk barrier, the holes through which they intend to slip through suddenly shrink down in size in between cuts, and Gizmo thus gets conveniently stuck.
Continuity mistake: When Beast Boy and Gizmo run into Cyborg's white blood cells, their positions before the side canal suddenly changes. At first Gizmo is at the left of the opening and Beast Boy to the right; but just before they run for it, Beast Boy is on the left and Gizmo is on the right.
Continuity mistake: When Cyborg infects the soda machine, there is a young man standing in the background. But when Cyborg races off to the transmitter dish and the soda machine starts spitting out its contents, the young man suddenly disappears from one moment to the other.
Chosen answer: It is located in California, as shown in "Teen Titans: Trouble in Tokyo". Possibly San Francisco as seen in the comics.
MasterOfAll