The building's fluid, wavelike walls are a true feat of architectural ingenuity.

Mysterious hillside with a continuously burning natural fire.

A shrine of fire worship built on top of a natural flame.

Home to nearly a third of the world's mud volcanoes, Azerbaijan is home to a messy, bubbling, and sometimes explosive landscape.

A massive collection of petroglyphs dating back some 40,000 years.

This African beach is home to thousands of rare mainland penguins that are known for their annoying voice.

An odd little fishing town that is inundated by tourists looking to be locked up in a cage and surrounded by great white sharks, because why not?

This small monument marks the divide between the Atlantic and Indian Oceans at the southernmost tip of Africa.

Earth's tallest volcano is sacred to Native Hawaiians, and home to a dozen world-class observatories.

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

This legendary urban waterfall creates a dazzling display of rainbows.

This black shoreline is made up of exploded lava particles.

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

A controversial memorial at the place where Captain Cook met his violent end.

One of the tallest buildings in Africa provides a great view of Johannesburg's unique geography.

Mount Nyiragongo has erupted at least 34 times since 1882 and is home to the world's largest lava lake.

The home of half the world's population of critically endangered mountain gorillas.

A strangely forgotten claimant to the much contested title of "Source of the Nile."

Founded as a refugee camp, now a popular tourist spot.

A 125-meter long "tribute to the Brazilian people."

As one of the world's largest hydroelectric dams this plant took two countries to get built.

A series of waterfalls so massive they straddle the border of Argentina and Brazil.

These spectacular ruins were built by Spanish padres in the 17th century.

Of the many Jesuit missions in South America, this complex is one of the best preserved.