The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

A beautiful but toxic fountain of mercury.

A massive, heart-shaped, wind-carved crater in the middle of the Israeli desert.

Dramatic river bend surrounds a natural red-rocked pedestal.

Most-visited and most-photographed slot canyon in the American Southwest.

The largest island on the great salt lake is home to curious creatures and strange stories.

This rugged area of red rocks and arches is often considered one of the most beautiful places on Earth.

One man has installed bathtubs into the Utah desert floor to harness the powers of a natural hot spring.

An urban laboratory.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

American revolutionaries and British soldiers alike are buried here in the fourth-ever cemetery in Boston.

The American Revolution was galvanized into serious action due to the tragic clash with British soldiers that occurred at this location.

An old trolley bridge was converted into a breathtaking garden bursting with colorful flowers.

Over fifty whirling pools left by the glacial age.

Ice cream stand, snack bar, and time capsule of milk conveyance.

The world's largest piece of copyrighted artwork.

A former waterfront market is now in the center of town due to some interesting Boston engineering.

On a former island, this old fortification once used to protect the Boston Area and started Edgar Allan Poe in his military career.

"the sweltering inhabitants of Charleston and New Orleans, of Madras and Bombay and Calcutta, drink at my well . . . The pure Walden water is mingled with the sacred water of the Ganges."

Rising 30 feet in the air atop Quarry Hill, the Old Powder House is the oldest stone building in the state of Massachusetts.

This bridge was the birthplace of a unit of measurement based on a fraternity joke.