A 19th-century time capsule of travel, fiction, and historic texts still available to the public.

The remnants of a depressing public toilet are now a hub of ever evolving street art.

Saintly bones pressed into a wax effigy of a Catholic superstar.

Commonly acknowledged as the only public monument to the Devil himself.

Vibrant street art created with mixed media.

A former steam-powered mill from the 1800s is now an industrial park with a giant steel dragon slide.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

The oldest giants in Catalonia are now displayed in a 14th-century Gothic church.

Possibly the oldest church in Barcelona, this basilica has its pagan and Christian mythologies all mixed up.

This former Baroque palace on the historic Calle Montcada is a rare architectural gem and was once the meeting place of an aristocratic scholarly society.

For one day every month Barcelona's Estació de França transforms into a market for model trains.

An exclusive waiting room built for the royal family in the 1920s is hidden in Milan’s central station.

The mummified relic of St. Antoninus.

This strange bovine gargoyle is said to have been put in as a passive aggressive form of revenge.

More sculpture than building, this architecturally significant temple was built on the spot of Saint Peter's crucifixion.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

The "Greatest Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

The yawning maw of this pagan visage is said to bite off the hands of liars.

The underground sanctuary of a mysterious ancient cult.

This former Roman Catholic Church still contains the embalmed hearts and organs of 22 popes.

Installed in an act of one-upsmanship, the annual sundial in this church is also a symbolic victory for the Gregorian calendar.

Architectural monsters are devouring this palace's every door and window.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

A hospital where antique dolls are given new life.