To find the enchanted islands, you must leave mainland Ecuador and travel west for 1,000 kilometers (620 miles). Follow the Equator to a patch of sea. There you will find an isolated clump of islands, the Galápagos.

From the air, some islands look like green gems atop the blue ocean. Other islands look barren. There are 13 large islands (12 shown on our map), six smaller ones, and scores of unnamed rocks. How did these islands form? The answer lies in the large plates that make up Earth’s crust.

From the Depths

The Galápagos Islands sit on top of one of Earth’s most active volcanic regions. The islands lie on the Nazca tectonic plate, which is touched by four other plates.

This place rests above a hot spot in Earth’s crust. Here, a column of hot magma rises. When it reaches the surface, lava spews out and piles up. Eventually, a volcano forms.

This is how the first Galápagos island, Española, formed more than three million years ago.

This aerial view shows the volcanic craters of Isabela Island.

On the Move...

Volcanic activity explains how one island formed. But how were the other islands formed? Tectonic plates move. The Nazca plate moves toward the South American plate at around 7 centimeters (2.7 inches) per year.

The hot spot does not move. Over time, Española was carried southeastward along with the Nazca plate. Then a new island— San Cristóbal—formed on the hot spot. The islands’ layout reflects the speed and direction of the moving plate.

map of Earth's tectonic plates

...Over Time

In a million years’ time, the island Fernandina will have moved 60 kilometers (37 miles) southeast. New islands will have formed in its place. The eastern islands are all older.

Moving Islands

It took millions of years for the Galápagos Islands to form. As the Nazca plate moves, new islands form over the hot spot. Old islands fall away into the sea.