The Aswan High Dam controls flooding of the Nile River.

The United States has no official language — English is the dominant language but is not legally designated.

Venice, Italy is built on 118 small islands connected by over 400 bridges and is slowly sinking.

The Andes Mountains are still rising today.

The Sahara Desert is roughly the size of the United States.

Greenland is the world's largest island — Australia is considered a continent.

The Colosseum in Rome could hold between 50,000 and 80,000 spectators and had a retractable awning called the velarium.

The Great Lakes contain about 20% of the world's surface freshwater.

The Millau Viaduct in France is one of the tallest bridges in the world.