The mysterious large white cross visible from the runway is a memorial to a massacre during Spanish Civil War.

Collection of nearly 500 concrete figures sculpted by the late Veijo Rönkkönen.

The gorgeous entrances into the city's underbelly look more like grand halls than subway stops.

Perhaps the tiniest sculpture in Saint Petersburg is a little bronze finch inspired by a song.

300-year-old villagers houses and traditional churches preserve a nearly lost piece of Russian history.

A floundering Polish shipyard was once the soul of the Solidarity movement that capsized communism.

A small part of Russia that does not touch any other part of Russia.

The reason for the strange contortions in the trunks of these "drunken" pine trees in Russia is still a mystery.

A shrine-like museum entirely dedicated to soccer superstar Cristiano Ronaldo.

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

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

An ever-growing literary collection housed in the apartment where the Russian author penned his final novel.

The 2,000-year-old Roman columns are hidden within Barcelona's Gothic Quarter.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

This symbol of Polish heritage survived the occupation during World War II, hidden in plain sight.

A tiny church on a man-made island in the Adriatic.

The old fire station features a mural that has more to it than first meets the eye.

A full figure 4th century incorruptible saint lies in a glass coffin in Croatia.

The tallest hotel in Europe.

It houses the remains of a 17th-century version of the Titanic.

This bridge was constructed from the rubble of the infamous Bastille.