The collapse of the extinct volcanic mountain Monte Gordo formed a caldera, locally called the Caldeirão. It is 3.7 km in circumference and 300 meters deep, and contains the Lake of the Caldeirão. There, you can observe several ponds and bogs, as well as two long and five small "islands" in the lake. “Morro dos Homens”, is the highest point of the island and lies along the southern edge of the Caldeirão at 718 meters above sea level. In addition to this peak, there is also: Lomba Redonda (486 m), the Coroa do Pico (267 m), the Morro da Fonte (371 m), the Espigãozinho (598 m) and Serrão Alto (663 m), an integral part of the geology of the Caldeirão.