Colorful and chaotic stacked hotel in North Holland.

'The Letters of Utrecht' lays out a ribbon of poetry one letter at a time, with no final verse in sight.

The world's largest bicycle shelter can hold more than 12,500 two-wheelers.

This Netherlands museum holds a gloriously mechanical collection of ornate musical automata.

An officers prison camp believed to be impregnable by the Germans saw over 30 successful escapes.

This incredible stone temple is a monument to death, victory, and fantasy architecture.

One of the most iconic neon ads of former East Germany.

This architecturally eclectic early-20th century mosque was built as a place of worship for the Islamic followers of a Jewish messiah.

One of the most photographed locations in the entire city.

The ancient abodes are a testament to human ingenuity amid harsh climates.

This hunter-gatherer architecture is believed to be the oldest religious complex known.

A sacred lake with thousands of sacred carp and a biblical history.

Mausoleum and Holy Seat of Antiochus I of Commagene.

The best-preserved ancient theater in the world.

This arch granting triumphal entrance into Antalya was designed to honor the emperor's visit.

Flames have been burning within this mountain for more than 2,500 years.

Roman ruins, natural methane fires and a lovely beach.

These tombs were built into the side of a mountain so that ancient angels could reach the dead.

A tiny park in the middle of some big power politics.

Ancient serpentine sacrifice holder that has stood the test of time.

A fountain standing as a testament to a doomed alliance.

This crucial gathering spot along the "hippie trail" still displays old notes between traveling beatniks and backpackers.

Legend says if you stick your thumb in the hole and it gets wet, your wish will be granted.

This column celebrates Rome's victory over the Goths, and may be the oldest Roman monument in Istanbul.