This large neolithic tomb, also known as Greengraves, is hidden off a Northern Irish road.

The only Bahá'í house of worship in North America and one of only a handful worldwide.

This lakefront cottage was crafted in the 1800s and was once a sanitorium.

A once extravagant mansion, now reduced to ruin.

This otherwise innocuous bodega was once the headquarters of the most feared assassin's guild in American history.

This unique bed and breakfast was first constructed during the 1800s by a Russian immigrant family.

One of the oldest living oak trees in the Southeast.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

Baked in 1898 and still almost flawless, this floral masterpiece is considered the world's oldest complete wedding cake.

This bell is one of the last remnants of the lost city of Triadelphia.

A remnant of the last Ice Age, this lake is surrounded by fascinating rock formations.

A fantastic example of Victorian railway engineering with two unusual decorative features.

Of all the unique artifacts inside this library, a mummified hand stands out among the others.

The Cathedral of Salamanca has a number of unusual carvings but none so surprising as a modern astronaut.

Buildings from the fictional planet of Tatooine still litter the Tunisian desert.

Fifty years after a “blast blasted blubber beyond all believable bounds,” this idyllic natural area commemorates the carnage.

In the 1930s, a mysterious murder shook this Northamptonshire village–the identity of the victim remains a mystery to this day.

America’s oldest community theater, this Boston club has been in operation since 1877.

The remains of the last Gonzaga villa, a luxurious palace built in spite of an economic crisis.

During the 19th-century, this park was a vital trading fort.

This partially buried wreck is one of the most complete of its kind but is only revealed when the sea allows.

All that remains of the fishing-vessel-turned-warship is its weathered hull.

This remarkably intact, 260-year-old cargo ship is only visible at the lowest of spring tides.

The stunning remnants of this wreck emerge from an otherworldly backdrop of rainforests.