The Racing Drones' Headquarters are the current base of operation for the Racing Drones.
In World Race the Drones' had not taken over, or even resided in Hot Wheels City. It was the final track in Highway 35 and contained the Wheel of Power. After Dr. Tezla decides to put the Wheel back a battle between the humans and the drones ensues. Ultimately Vert Wheeler is able to put the Wheel of Power back in the City.
After World Race the Drones somehow take over Hot Wheels City, and therefore capture the Wheel. Dr, Tezla tried to take the Wheel in the beginning of Ignition, but is shot down by a drone, before he was killed, Tezla used an early prototype of the E.D.R. to leave for Highway 35. For the rest of the series the City is the place where Gelorum and her drones reside, creating more drones, cars, and copying Accelechargers. In Ultimate Race during the effort to save Markie, all drivers but Vert (for entering the swamp realm) realms and hijack a sweeper to get into the captured City. There they find Kadeem and Markie. Both of which were turned cyborgs. Once Markie was saved the group left the City, along with the Silencerz secretly taking the Wheel of Power for themselves. It is unknown what happens to the city afterwards. It is presumed the city still stands at the end of the series although most likely it is uninhabited.