Wedged between two buildings at the Great Ormond Street Hospital is this secret music installation.

A subterranean ice warehouse that has lain hidden beneath central London for over a century is now open to the public.

Banksy gives themself artistic license with this piece of London street art.

An unusual round church in London with a Templar past.

A kaleidoscopic warehouse-maze of handmade neon signs.

This collection of illusory paraphernalia has been culled from the history of London's premier magician's club.

A sinister pyramid in the Frari contains the heart of the famous neoclassical sculptor.

100 year tradition of fist fights, marked by marble footsteps.

A complex, nine-layer maze on the grounds of a Venetian doge's playground.

The world's oldest surviving anatomical theater, where "the dead are pleased to help the living."

This half-finished "city of toys" was almost Italy's own Las Vegas.

Crumbling ruins of the thermal baths that once attracted royals and aristocrats from throughout Europe.

This Italian foot path winds through the mountains via 52 individual tunnels.