A tunnel with windows, so you don't miss out on the impressive views.

This black shoreline is made up of exploded lava particles.

A beach made of semi-precious green sand on the Big Island of Hawaiʻi.

The southernmost point in the United States is a beautiful place to look at but a deadly place to wade in.

Football field-sized microalgae production tanks on the Hawaiian coast create a stunning view from space.

These picturesque Hawaiian falls are home to a rare species of fish that uses a special sucker to climb up cliffs.

Hide from the tourist hordes in these relatively unknown, and unguarded lava caves.

Race through the maze, get your name on the sign.

On Waikīkī Beach, a monument to four extraordinary individuals of dual male and female spirits who brought the healing arts from Tahiti to Hawai'i.

Hawaii’s largest cemetery rests inside an extinct volcano crater.

This little sun pays homage to a massive gate that once stood at this location.

This sweet-toothed bear searching for snacks has been a symbol of Madrid for decades.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

This magnificent castle grew from a small Moorish fortress, and reportedly inspired two iconic Disney castles.

Once the grandest synagogue in medieval Spain, it now stands as a memorial of the 15th-century Jewish exile.

This bronze boar's snout has been rubbed to a golden sheen by visitors seeking good fortune.

Secret refuge and museum of the Duke of Florence.

Over 50 exquisite hand-painted Renaissance maps decorate a Medici storage room.

In Florence's great Duomo, a 26 foot fresco honors a mercenary famous for attacking Florence.

The mummified relic of St. Antoninus.

Erotic art covers the walls of the largest ancient pleasure palace.

This amazingly preserved Doric temple was abandoned before it was ever completed.

Two of the few remaining life-sized Greek bronzes were submerged in the sea for over 2,000 years.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.