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

This giant wooden treehouse within a sprawling garden has its own eatery.

This iconic 1,000-year-old medieval castle is a favorite of the film industry, most notably as the location for Hogwarts in Harry Potter.

This enchanting Victorian estate was home to the world's first hydroelectric power generator.

Beneath the city of Lourdes, France is a massive, concrete church.

Ancient paintings known as the "Sistine Chapel of Cave Art."

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

Remains of the artificial harbours invented for the Allied invasion of Normandy can still be seen at sea.

These unique markers designate the route American forces took during the Liberation of France.

An effigy of a trapped paratrooper dangles from a Normandy church to commemorate one remarkable D-Day event.

This enormous "cloth of the conquest" depicts the Norman invasion of England in mind-blowing detail.

This community on a small Venetian island has taken to painting their houses in bright neon hues.

This one-time health resort was used by aristocrats around the world.

Climb to the top of the world's largest seated bronze Buddha.

The world's longest outdoor covered escalator system transports commuters through Hong Kong's hilly terrain.

This gem-encrusted temple is said to contain some of the Buddha's hair which can make the deaf hear and the blind see.

Macabre astrological automaton clock dating to the late 1400s.

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

The metal leaves on this tree are engraved with the names of Holocaust victims.

The mummified right fist of a 1,000-year-old saint-king sits inside an ornate golden reliquary.

A unique museum dedicated to culture and artistry of carpet weaving.

This mysterious but iconic tapered tower appears in many Azeri fairytales and legends.

Destruction from Armenia's 1988 earthquake inspired an artist's sculptures of scrap metal.

Nestled in a peaceful valley, this Armenian monastery may have been saved from Mongols thanks to the eyes of God.