A unique art installation located on what was once considered the widest railway bridge in the world.

Glasgow's memorial to the International Brigade volunteers from Great Britain who fought and died in the Spanish Civil War.

A scattered trail of street art adds a pop of color to the city's stark structures.

Displaced highlanders would take shelter from the wet Scottish climate under the large walled bridge at Glasgow Central Station.

This vessel is the final ocean-going paddle steamer in the world.

A fernery hidden by neglect is uncovered, and an ancient specimen along with it.

A stone copper was sculpted on the wall of the Carlisle Cathedral to honor a local hero.

Hidden under a shopping centre is the genesis of modern Liverpool.

On the outside of the Mersey Tunnels, an Art Deco sculpture of an Egyptian Pharaoh wears goggles and racing gear.

A plinth outside a church displays sculptures by local artists.

Most of Britain's gold reserve was secretly stashed here after the start of World War II.

This stone once marked the boundaries of Liverpool's medieval markets.

This aging storage facility is the world's largest brick warehouse.

This bronze statue was dedicated to a 1966 Beatles hit.

The tower was originally used as a chimney for the waste incinerator of St Johns Precinct and Market.

The red letters in the literary pavement leading to the library form a mysterious code.

A monorail that was built to serve a new development but technical problems, lack of users, and a pandemic caused it to be closed and abandoned.

No one is sure what to do with this WWII shipwreck that sits at the bottom of the Thames, still loaded with tons of explosives.

This abandoned gun tower was built to defend the River Thames from a French naval attack.

Surreal riveted sea forts once protected the Kent shores from German attack.

The world's most active stratovolcano is almost always erupting.

A quiet museum preserves the extraordinary relics, processional treasures, and centuries-old traditions behind Catania's famous Feast of Saint Agatha.

This elegant black and white striped arch is emblematic of Catania's resilience to natural disasters

Wedged between streets and buildings, this ancient Roman theatre could seat 7000 spectators.