This poured-concrete water reservoir is a gem of modernist architecture well-hidden in a city forest.

Every summer, an open-air swimming pool appears at the base of a Finnish city's beloved winter attraction.

A rare surviving Victorian greenhouse designed specifically to house giant water lilies.

A temporary art piece to celebrate LGBTQ Pride is now a permanent part of Stockholm's traffic landscape.

Every Tuesday, students let off steam by screaming into the night air.

A statue that stood at the center of a long copyright battle.

This tree was once used to calculate the decrease of the Baltic Sea.

This structure atop a craggy cliff in one of the most beautiful parks in Paris boasts an unbeatable view.

Paris' linguistic guide to the international language of, yes, love.

An immersive projection art installation uses sound, scale, and light to take visitors inside classic works of art.

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.

Known as the "Dodo Manège," this carousel features a herd of animals that have disappeared—or may be gone soon.

The first green space constructed on an elevated viaduct.

The narrowest street in Paris.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

This former “ante-chamber to the guillotine” has been refurbished to illustrate the brutal history of French justice.

This modest marker near Notre Dame identifies the very center of Paris.

Notorious artist squat renovated into legal studios.

A 16th-century fountain marks the site of a lost medieval cemetery once filled with mass graves.

A Parisian exterminator's shop whose storefront displays stuffed rats hanging from traps.

A mechanized clock where a man fights off a dragon, crab, and rooster.

France's national museum of scientific and industrial instruments.

A French artist's vague warning hangs over Belleville.

This Paris art space celebrates the creativity and ingenuity that springs from abject poverty, especially in Africa.