Once a resting spot for King Fernando VII.

The remains of the second-oldest zoo in Europe can be seen within these library gardens.

One of the "twins" in these falls on the Snake River was sacrificed for hydropower generation in the 1930s.

This pair of unsuspecting buildings are in fact the very first modern skyscrapers in Europe.

The only bridge in the United States where BASE jumping is legal without a permit year-round.

A geothermal paradise with bubbling mud pools and bright blue hot springs.

According to local legend, this church was built with two doors, so that residents of two rival villages had their own entrances.

This memorial to a murdered empress took 20 years to design, then spent 30 years hidden away in storage.

One of Serbia's oldest luxury hotels and a nostalgic echo to Yugoslavia in the state's former capital.

These abundant, over-the-top monuments are so widely scattered that they define the entire compact capital cityscape, often leading to jokes about whether there are more statues than residents.

Liechtenstein's royal family calls this medieval alpine castle home.

Ramsgate’s Royal Harbour has the unique status of being the only Royal Harbour in the United Kingdom.

A statue built to honor the elite soldiers who fought for Latvia during World War I.

The lighthouse is on a island which is connected to another island, which is connected to another island, which is connected to one of the largest islands in the world.

Legend has it the lovelorn tears of a princess and a shepherd boy formed the blue and green twin lakes in the Azores archipelago.

These 400-year-old ruins are all that's left of the monastery where Ines de Castro was assassinated by the King of Portugal.

One of few vertical lava tubes in the world accessible by foot.

Eat the ultimate iteration of Portugal's most beloved pastry.

This glass skywalk offers vertiginous views down the volcanic cliffs to the beach below.

An intricately decorated tiny place of worship.

The largest fountain in Bratislava.

This spaceship sculpture in the middle of the Slovakian capital looks like it just crash-landed.

This crumbling medieval basilica once attracted pilgrims by the thousands to collect a miraculous dust that formed above the saint's tomb.

The ancient latrines of the Greeks, in all their public glory.