Transport for London has just announced that changing between lines at Bank tube station will not be possible from the end of this month until the middle of next year.
The only exemption is between the DLR and the Northern line – which is a bit of a pain for me as I usually switch to the Central line on the times I take the DLR into town and don’t get off and walk the rest of the way.
As the entrances are not closed off, I presume you can go up to street level and then back down to the line you want.
It also coincides with the closure of Tower Gateway this summer, so people getting to/from the City are going to have a great time this year.
Bank is not, as is often reported the deepest tube station on the London Underground in terms of depth below sea level, that acolade goes to the Northern Line platforms at Waterloo station. However, thanks to hills in Nth London, the deepest in terms of distance from surface to station is Hampstead station on the Northern Line (again!).