Latin America is divided into three main regions - Mexico and Central America, the Caribbean, and South America. Mexico and Central America feature mountainous terrain like the Sierra Madre mountains. Central America is an isthmus connecting North and South America crossed by the important Panama Canal. The Caribbean is composed of islands, both volcanic and atop sunken mountains, surrounded by the Caribbean Sea, an important trade route. South America is defined by the Andes Mountains along the western coast and the immense Amazon River basin and rainforest in the center.