The largest freshwater lake in the Florida Keys.

A monument celebrating the idea of reaching inaccessible places.

Stay in a room with a view... of the bottom of the ocean.

Secret refuge and museum of the Duke of Florence.

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

This freshwater spring fills with 10,000 gallons of water per minute.

Largest lake in Great Britain measured by surface area.

Largest Roman Catholic church in North America.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Burial grounds for more than 1,000 bodies deep under the modern town of Rabat.

The final resting place for the remains of 143 Habsburg royalty.

Morocco's largest Jewish cemetery.

Traditional 11th-century outdoor tannery.

World's largest bell sits on the grounds of the Kremlin in Moscow.

The tower was originally used as a chimney for the waste incinerator of St Johns Precinct and Market.

The capital of the Cayman Islands is a center of offshore banking, but gets battered by blistering hurricanes.

Abandoned Roman Catholic chapel abused by Satanists before being restored.

Synagogue built from the stones of Solomon's temple contains the golem of Prague.

The Guardian of Tallinn.

Some of the world's only freshwater seals live in one very special lake in Russia.

One of Europe's oldest libraries.

The mummified right fist of a 1,000-year-old saint-king sits inside an ornate golden reliquary.

This building holds the embalmed remains of the leader of the Bolshevik Revolution.

A snapshot of the city's fascinating voodoo culture.