On Japan's Tashirojima Island, cats are king.

An exquisite tunnel of cascading flowers.

The picturesque birthplace of Icelandic democracy is drenched in the blood of its brutal past.

A fantastic reconstruction of a 10th-century Viking longhouse.

Travel deep inside of Europe's second largest glacier in the world's largest man-made ice cave.

A magnificent collection of imperial armor and weaponry.

Former utopian colony based on the belief that the universe exists in a hollow sphere.

An abandoned settlement originally established by British colonialists in the Andaman archipelago.

Despite its ornamental looks, this towering Tuscan-inspired anomaly was a masterpiece in hydraulic engineering.

Gothic tower mentioned in Thomas Hardy poem "The Channel Firing."

Also known as Rye Castle, this 13th-century fortification later became a prison and held one of Rye's most famous criminals.

Henry VIII's forgotten castle was built by the gunpowder-obsessed king to be defended solely by cannons.

This centuries-old hotel hides a network of secret cellars and passages once used by smugglers.

This striking observation tower shaped like a spinnaker sail is the newest icon in historic Portsmouth.

This floating garden in the sky is straight out of a fairy tale, but the real thing is nothing short of magical.

The solitary cairn marks a mysterious death that's still controversial more than two decades later.

A gated cross stands on the site where an Irish revolutionary met his end.

This observatory within Europe's first dark sky park offers stunning views of the night sky.

An optical Illusion once believed to be an electrical phenomenon.

Standing atop Wellington Hill is the world's tallest three-sided obelisk.

Never actually a tree at all, this spot was the site of London's public hangings for nearly 600 years.