An elliptical glass tower that is known as the world’s first two-sided building.

This sycamore is Connecticut's largest tree, New England's largest sycamore, and among the largest of its kind nationwide.

The former location of a platform that allowed passengers to safely wait for the trolley.

The last vessel built by a submarine pioneer stands as a monument to his legacy.

A preserved trolley track that was transformed into a museum of transportation.

This Connecticut ferry has been operating in some form since 1655.

A unique work of art that was created without permission.

The purported world's shortest international bridge connects a homeowner in Canada to his backyard in New York.

A castle built for love, and abandoned due to heartbreak.

The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

The famous sculptor had a hand in this imposing fortress.

Sky ships, planes, and portraits left as unique tokens of hope and thankfulness.

This historic island prison holds one of the dungeons from the Count of Monte Cristo even though it is a work of fiction.

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

The world's most active stratovolcano is almost always erupting.

An enigmatic modern marker left next to a historic Roman site.

An abandoned building that once tightened a power line that stretched across Messina Strait.

Climb the dead electric pylons of Messina.

Depending on how it is measured, this lighthouse can claim to be the tallest in Europe and the tallest conventional lighthouse in the world.

This cathedral hides a sculpted dog that determines your fate and an unexploded shell from World War II.

Once home to one of the oldest banks in the world, this building is also where Marco Polo's famous travelogue was written.

Massive galleon from a box-office bomb docked in Genoa.

A cemetery in Barcelona's Poblenou district is home to this touching funerary statue, which depicts death in the form of a winged skeleton.

An early 20th-century bullring converted into a modern shopping center.