A 1,215-foot tunnel transports pedestrians beneath the River Thames.

The remains of Crystal Palace Great Exhibition of 1851.

Abstract dinosaur models in London.

Shakespeare, David Bowie, Dr. Who, the Saxons, Druids and Romans are all claimed to have all made their mark on these massive man made tunnels.

The Origin of On the Origin of Species.

Grotto replete with mystical designs laid out in glued shell mosaics.

One of the few standing Roman lighthouses and a labyrinth of tunnels are a couple of the secrets at this historic castle.

This elaborate temple was built around one of the Buddha's teeth.

An ancient stone fortress considered by many to be the eighth wonder of the world.

The silly symbol for an underground protest group is now scattered around the city.