Mosques carved from coral and dozens of well-preserved stone structures fill this 500-year-old Swahili trading center.

This slowly crumbling mansion was home to one of East Africa's richest and most powerful slave traders.

In Zanzibar, a historic 19th-century palace is a reminder of the world's shortest war.

This sacred, circular cave is lined with pools so clear and still that it's hard to tell where the water begins.

Stay in your own little bubble.

Stunning ruins of what was once the center of one of the greatest empires in East Africa.

A salty red wasteland in Tanzania is a breeding spot for endangered flamingos.

One of the largest early 20th-century bridges in Sudan.

The best-preserved example of a unique structure in Nubian architecture.

Crumbling pyramids and temple ruins stand within the shadow of this sacred butte.

Remains of an abandoned coral city.

These Nubian pyramids are strange and unique, even by pyramid standards.

Every October, one of the largest migration of mammals in the world thunders through Boma National Park.

The inhabitants of the world’s largest wetland have learned to navigate its dramatic seasonal changes.

The haunting beauty of this little-visited wreck makes it a true hidden treasure.

An abandoned water park overtaken by the dunes.

Is this 200-meter-wide nature reserve the smallest desert in the world?

A giant concrete Brutalist water tower in suburban Johannesburg.

This cave overlooking the Indian Ocean has been turned into a shelter and makeshift museum.

This beautiful waterfall is not easy to reach, but offers a stunning view of the pristine green valley.

Brace yourself for the slowest, scariest, most spectacular drive, down the Drakensberg Escarpment.

Despite many attempts to finish this overpass, it has been abandoned since the 1970s.

Mined to a depth of 240 meters with a perimeter of about 1.6 km, the largest hand-dug excavation in the world.

An ancient impact crater on the outskirts of Pretoria.