A stunning mosque owes its design to an Ottoman ruler nicknamed "the Butcher."

This unassuming oasis elevated just above the busy streets of Jerusalem offers one of the best views of the Old City.

The only quarter of the Old City not dedicated to a major world religion.

Neighborhood in Jerusalem is home to the ultra-orthodox haredim.

An ancient underground cultic temple where sunlight penetrates on the summer solstice.

This daunting 1st century fortress was purportedly the site of one of the most dramatic revolts of the Jewish-Roman wars.

Extremely famous in his native country, this Cracovian painter is all but unknown beyond Polish borders.

An artificial date palm stands as a memorial to Warsaw's Jewish community.

In the summer, the area around this sculpture transforms into a vibrant concert venue.

This enormous 32-foot painting depicts Poland's greatest medieval battle in glorious detail.

At first glance, this area seems like just another city park, but the lush landscape hides a dark past.

This fairytale medieval church in Poland originally spent centuries in Norway.

A memorial to the beloved brown bear that served in the Polish army during World War II.

The Polish capital has had a deep connection to its guardian mermaid for almost a millennium now.

A tribute to the Polish insurgents who fought in the failed attempt to end their city's Nazi occupation.

The ritual has been performed uninterrupted for nearly 700 years.

These docile dragons are ideal inhabitants for the conservatory greenhouses.

The library houses an incredible collection of some of the world's most impressive books and manuscripts.

These official units of measurement—including chains and perches—lie hidden beneath tourists' feet in a popular London hub.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

The rose garden in Regent's Park where Pongo and Perdita met for the first time in Disney's "101 Dalmatians."

Local legend says Isaac Newton built this footbridge without any screws, bolts, or nails.

Famously misunderstood wonder of the ancient world

The oldest working mechanical clock in the world.