A preserved oak tree about 3,500 years old found in Riga, Latvia.

Flamboyant architecture from the turn of 20th century.

The oldest housing complex in Riga is a mini timeline of architectural trends.

3,000 market stands in five former Zeppelin hangars.

A former Latvian headquarters of the brutal KGB secret police is now open as a grim reminder of their atrocities.

Modern art commemorates one of the first military actions of World War II.

A mysterious emblem tucked in an small alleyway is actually the coat of arms of a heroic medieval family.

A merchant court dedicated to the fictitious King Arthur is heavily adorned with bizarre Renaissance art.

A huge wooden clock that is so beautiful its creator was forcibly blinded.

The site of the first battle of World War II.

This Bordeaux parking garage has 712 indoor spaces, and one outdoor.

The world's largest reflecting pool is just two centimeters deep.

Eighty million natural history specimens call this gargantuan museum home.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

A Gothic cathedral created from volcanic rocks.

The sunken structure looks like the victim of a catastrophic flood.

Do these monsters look familiar? The gargoyles on this church are all from pop culture.

A massively oversized measuring tape sculpture sits inside a hidden yard.

This small island, a byproduct of 19th-century canal construction, is now home to a charming Japanese garden.

Home to the "Rat King" of Nantes and other wonders of the natural world.

Massive puppet-automaton machines created by French artist collective Machines de l’Ile.

A very uncommon water tank standing in the middle of the grapevines in Bordeaux nearly a century after its construction.

Straight out of a nightmare, barcode-faced babies climb up and down Prague's television tower.

Steadily reminding Czechia of its past.