Tower with a double-helix spiral, adorned with letters of the Georgian alphabet.

A shipwreck named Desire at the shore of Batumi.

Why have you never heard of the second most popular tourist site in New York?

A once grand hotel is being retaken by the wilderness it once capitalized on.

The only intersection in America where the buildings on all four corners were built pre-Revolutionary War.

The life of one of FDR's possible mistresses is preserved in her palatial Hudson Valley mansion.

An unassuming island in the middle of the Hudson that hosts campers, including Aleister Crowley.

This stone gatehouse was once the entrance to a historic mountain resort, and it had a cameo in a cheesy cult horror movie.

This bridge was the birthplace of a unit of measurement based on a fraternity joke.

These unassuming lighthouses have seen the first reading of the Pledge of Allegiance, the first wireless transmission, and more than one mystery.

A dark patch of the ceiling at Grand Central Terminal which was not restored is still stained brown by tobacco.

Fire meets ice at the southernmost volcano on Earth.

A temple to modernity, tucked away amid Barcelona's more well known museums.

Formerly known as National D-Day Museum, this collection commemorates the battles of Normandy and WWII.

The land is home to swimming ponies and a legendary 18th-century treasure.

This monument on Breed's Hill proves that one of the most famous battles of the Revolutionary War is misnamed.

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

Mysterious 500-year-old tapestries depict a unicorn hunt.

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

A dramatic, 360-degree recreation of Pickett's Charge in the Civil War.

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

I-95's Tijuana-style celebration of kitsch at the Carolina border.

The deepest lake in the United States, and once the site of epic destruction that lives on in legends.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.