Single runway interrupted by a busy road that cuts across its middle.

Red, white, and blue painted steps along with a Union Jack celebrate the outcome of Gibraltar's 1967 referendum.

Natural stone arches form a walkable "cathedral" at low tide, then disappear entirely when the water returns.

Stormy conditions send jets of seawater bursting through holes in the cliffs.

A charming Spanish village sits atop this natural limestone overpass.

This religious complex carved into a cliff is steeped in legends of miraculous stags and the Holy Grail.

An abandoned socialist utopia built in the late 19th century.

The castle where Martin Luther secretly translated the New Testament from Greek to German while in hiding.

Made from trees and then abandoned, this fence is still growing along a path in Germany.

Oberweissbacher Bergbahn - a broad-gauged cable car capable transfering railcars.

"The most colorful grottoes of the world.

Bacteria and algae give the salty water its bubblegum hue.

This small Spanish village still pays homage to the Spaghetti Western films that were shot there in the 1960s.

This abandoned gold mine found a second life as a post-apocalyptic film set.

This tiny German village has staked claim to being the center of the union following Brexit.

A sprawling Baroque park with 300-year-old hydro-pneumatic waterworks.

This wrecked ghost ship has been rusting on a Greek beach since the 1980s.

The historic tower houses of this nearly abandoned Greek town have been compared to the spikes on an iguana's back.

Ruins of a 13th-century fortress perched above a breathtaking Mediterranean bay.

A magical, if a bit tacky, 1960s castle conjures up medieval fairytales and Greek mythology.

A 16th-century horror show built in a lovely Italian garden.

A 17th-century doorway in a small Sabine village is a portal into the mysteries of alchemy.

Romans built the world's tallest artificial waterfall in 271 BC.

When occupying Nazi troops detonated a mine below, medieval frescoes were revealed in this small cliff-side hermitage.