The largest greenhouse in the world is home to over one million types of plants.

A 16th-century horror show built in a lovely Italian garden.

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

St Bernard de Clairvaux Episcopal Church, better known as one of the oldest European buildings in the Western Hemisphere.

Acres of natural wonders left behind by a socialite-turned-gardener.

Ruins of the elaborate house where the enigmatic costume designer threw glamorous parties for New York's theatrical elite.

This dramatic landscape hidden on the Isle of Skye looks as though you've stepped into the magical realm.

Grotto replete with mystical designs laid out in glued shell mosaics.

The world's longest known cave system.

A museum to a cave explorer whose tragic death was a media sensation, and whose corpse became a tourist attraction.

Despite centuries of architectural innovation, this French castle is being built like it's the 13th century.

Site of a famous 19th-century transcendentalist utopian community, now abandoned.

Maybe the only missile installed in a public park, this Cold War leftover was one of the first to carry a nuclear warhead.

This Canadian monument to the man who invented the telephone allows visitors to get up close and personal with the artifacts of his life.

Site of the first official transatlantic wireless communications.

A giant white horse drawn on an English hillside may not have been intended to be a horse at all.

The longest hedge maze in the world.

The sign at the garden gate reads: "These Plants Can Kill."

A tiny museum housed in a New York freight elevator specializes in the "overlooked, dismissed, or ignored."

A collision of human error and natural geothermal pressure created this rainbow-colored geologic wonder.

The longest burning light bulb in the world.

A coastal rock outcrop with mysterious inscriptions variously attributed to Native Americans, Portuguese, Phoenicians, Norse, and more.

One car at a time please.

This chilly Canadian hotel has a four-month lifespan due to the unusual material it's made of.