In 2023, on a Tuesday, a rift appeared on Tower Bridge. It allowed through an orb of crackling energy which turned out to contain a time-shifted H. P. Lovecraft. Before it revealed its passenger, however, the orb damaged the concrete and several nearby cars, causing multiple casualties. As a result, police and MI5 forces closed the Bridge to the public and called in P.R.O.B.E. to resolve the situation. After P.R.O.B.E. helped send Lovecraft safely back through the rift even though he'd lost the protection of the orb, the portal collapsed in on itself. (AUDIO: Guardian At The Gate)
The map in The Lie of the Land shows the north end of Tower Bridge as being either within or close to the east of the City of London. When viewed in conjunction with the map of London boroughs seen in Revenge of the Slitheen, this would definitively place the southern end of Tower Bridge in Southwark.
Sources[]
↑The Next Doctor. Doctor Who - Season Four. Retrieved on 4 December 2018.