The Aral Sea — once the world's 4th largest lake — has almost completely disappeared due to Soviet-era water diversion.

The Mediterranean Sea connects Europe, Asia, and Africa.

The city of Venice is built on 118 small islands connected by 400 bridges.

The Earth is slightly flattened at the poles.

The Nile is generally considered the world's longest river, but some measurements put the Amazon ahead depending on source point.

The Ice Age featured massive glaciers covering large parts of Earth.

The Amazon River discharges more water into the ocean than the next seven largest rivers combined.

Greenland is the world's largest island.

The Great Lakes were formed by glacial movement.