A walkable map of the world, made from soil and stone by one man.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

Of the many chalices in the running for the Holy Grail, this one in Valencia Cathedral sure looks the part.

Mirrors and glass shards cover every inch of this arrestingly beautiful mosque.

A tongue-in-cheek arcade where the games are based on everyday life.

Europe’s oldest natural human mummy.

Walk through a fairytale in Tuscany.

An architectural marvel that spans the Arda River, and has stories of a haunted past.

A stunning bridge that appears as if it's lunging to the shore, and has a legend of a devilish architect.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

Known as the most dangerous bridge in the world, the Hussaini Hanging Bridge is only one of many precarious rope bridges in Northern Pakistan.

An alleyway plaque is all that remains of the independent Texas' envoy that forgot to pay their rent for over a century.

Residential building on the Regents Canal is a breeding ground for creativity and innovation.

This immaculate and historic water garden culminates in a massive stone dining table with an inset fountain for chilling the wine of the Cardinal's guests.

A large grotto built in the 16th century amidst Florence's famous Boboli gardens.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

Sitting on an Italian hilltop is this surreal fortress built by the mad inventor of electrohomeopathy.

The glowing blue Nymphaeum of Emperor Tiberius.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

Stalactites and stalagmites in a beautifully lit cave.

A tower built by an emperor for an antelope.

This grand Pakistani mausoleum can only be accessed via an almost 1,000 foot long alleyway.

Lunar landscape, a mud volcano and bizarre rock formations.

Unique pagan culture in three extremely remote mountain valleys.