Many parts of the island have been modified by human development since the arrival of coconut plantations in the 17th century, but it remains largely white coral sand with mangrove forest at its center.

Its eastern coast runs parallel to the northernmost stretch of the Belize Barrier Reef, a UNESCO World Heritage Site.

[1] It is widely believed that maritime trade motivated the Mayans themselves to excavate "Boca Bacalar Chico", the marine channel that separates the island from the Mexican mainland, but its origins could also have been natural (e.g. a hurricane).

Ambergris, from the Old French "ambre gris" (literally "gray amber"), is a rare substance produced in the intestines of sperm whales, valuable historically and in some modern perfumes as a fixative.

In the 17th century, whalers in the tropical Atlantic Ocean operated from many islands like Ambergris Caye, and although sperm whales are not considered residents of Belizean waters, the animals continue to pass through on a regular basis.