One of Catholicism's four major basilicas has a series of papal portraits that are said to predict the end of the world.

Italian poet Dante Alighieri is entombed in this small mausoleum in Ravenna, and his hometown of Florence has never been too happy about it.

These medieval skyscrapers dominate the skyline of this small Tuscan town.

This sword isn't waiting for a king to pull it out. It was placed there by a saint.

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

A black and white mural stands out from its psychedelic surroundings.

Crypt mausoleum in cathedral's basement contains relics of third century Roman martyr, Saint Vibiana.

An elaborate gift from Claus Spreckels is now a piece of San Francisco history.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

Relics of the 1894 Midwinter Exposition continue to delight visitors today.

A British plaque explains that a house was built using the spoils of the first international golf bet.

A 18th century graveyard and its astonishing cortege of macabre iconography.

The topiary maze at the Habsburg hunting lodge.

Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.

Baroque celebration of the end of the Great Plague of Vienna.

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

An exquisite Baroque church in Vienna's old town.

Op-art architecture designed for happiness.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

A "miracle" that seems to produce more holy fistfights than holy revelations.

An ancient necropolis of magnificent tombs.

Giant, friendly pelicans in Central London, the most unlikely of places.

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

The celebrated eyesore created by starry-eyed sweethearts.