The oldest still-operating tavern in the United States was once owned by a pirate.

This abandoned psychiatric hospital once housed more than 4,000 patients in the middle of a quaint New England town.

This opera house along the banks of the Connecticut River has two Tony Awards to its credit but it’s never staged a single opera.

New Preston and Kent, Connecticut - where Friday the 13th, Part 2 was filmed.

Quirky castle designed by the American actor best known for portraying Sherlock Holmes on stage.

An easy-to-miss plaque marks the building that first held this 19th-century telephone innovation.

The oldest place in Hartford is a cemetery with thousands of bodies stacked beneath the grass.

The former home of Samuel Clemens and family remembers the happiest period of the author's life.

Skulls and skeletons are omnipresent in this church dedicated to souls trapped in purgatory.

This secret coastal village is studded with pastel-colored houses all piled on top of one another.

Legend says this sacred tree was a gift from goddess Athena.

An ancient octagonal weather station named for the eight Greek gods of wind.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

Barça football fans might see the insignia hidden in a church window as a divine sign.

This stunning iron gate designed by Modernist architect Antoni Gaudí is filled with mythic symbolism.

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

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.

Museum celebrating the ocean, with the largest wunderkammer dedicated to sea exploration.

An ancient Roman temple first dedicated to an emperor's wife is now a church.

This one-of-a-kind Roman arch is not actually dedicated to the god Janus.

This small, ancient Roman temple was once a church dedicated to the patron saint of penitents.

This curious, round temple is the oldest still-standing marble building in Rome.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.