91Èȱ¬

The Maunsell Forts in the Thames Estuary, off the Kent coast, were built to defend London against German planes using the Thames to navigate in World War Two.

Abandoned by the military in 1955, the towers have barely changed since the end of the war.

Visitors are currently only allowed to take boat tours around the towers, but the 91Èȱ¬'s Ben Zand was given special access to climb on board and explore them.