This 6th-century church has the largest and best-preserved collection of Byzantine mosaics outside Constantinople.

Italian cave with exceptional acoustics and an unsavory history.

The remnants of a depressing public toilet are now a hub of ever evolving street art.

Manchester salvaged this sculpture of the adopted Mancunian when it was no longer wanted in Ukraine.

Be on the lookout for the symbolic insect all over the city.

Manchester's abandoned train depot lingers in a post-industrial purgatory.

Have a seat with the father of modern computing at this Manchester monument.

Dating back almost 400 years, the oldest public collection library in the United Kingdom was once the study hall of Karl Marx.

A proud bronze billy stands as an eternal symbol of Ireland's oldest festival, where a goat is made king.

A hugely vast Irish landscape of barren rock that stretches for miles.

This ancient Irish tower could easily have stood in for Rapunzel's prison.

This single room has survived the centuries with almost no deterioration.

This controversial Irish show cave is home to a massive formation known as the Great Stalactite.

The ancient tomb acts as a calendar that keeps perfect time.

The comedy and tragedy of Oscar Wilde is preserved in a Dublin park, captured in a sculpture of colorful stone.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

A living art gallery painted on a canvas of Monterey pine trees.

An archeological treasure trove stumbled upon by a couple of children.

Hundreds of stone stairs and a winding medieval bridge connect this haunting Spanish island to the mainland.

Two towns are linked by an engineering marvel masquerading as a boring suspension bridge.

This 19th-century fountain's namesake animal isn't what you think it is.

This demon atop the Notre-Dame de Paris looks utterly bored.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

This former “ante-chamber to the guillotine” has been refurbished to illustrate the brutal history of French justice.