1. Falls divided by Goat Island into American and Canadian falls.

Niagara Falls

2. The enormous gorge of the Colorado River in Northern Arizona.

Grand Canyon

3. A geological fracture in Earth's crust in California.

The San Andreas fault

4. A noted sea cave on the coast of the island of Capri, Italy.

The Blue Grotto

5. A body of salt water on the border of Israel and Jordan.

The Dead Sea

6. The most important mountain pass connecting Afghanistan and Pakistan.

Khyber Pass

7. Caves in southwestern France famous for prehistoric cave paintings.

Lascaux caves

8. Thousands of polygonal columns of basalt on the coast of Northern Ireland.

Giant's Causeway

9. Site in Tanzania where some of the earliest human remains have been found.

Olduvai Gorge