Fulham Railway Bridge
Fulham Railway Bridge crosses the River Thames in London. It is very close to Putney Bridge, and carries the London Underground District line between Putney Bridge station on the North, and East Putney station on the South. Fulham Railway Bridge can also be crossed on foot, on the downstream (east) side.

Fulham Railway Bridge crosses the River Thames in London. It is very close to Putney Bridge, and carries the London Underground District line between Putney Bridge station on the North, and East Putney station on the South. Fulham Railway Bridge can also be crossed on foot, on the downstream (east) side.
Check the official site before travelling; hours and prices can change.
More bridges

Tower Bridge
The bridge people mean when they say London Bridge. Walk the high-level walkway for the glass floor.

Millennium Bridge
Foot-only suspension bridge from St Paul's to Tate Modern — the only crossing aligned on St Paul's dome.

Hammersmith Bridge
Currently pedestrian-only, Victorian wrought-iron beauty — best photographed at golden hour.
Source: wiki-list