Pico Alto (literally high/tall peak) is a mountain which is the highest point, 586.84 metres (1,925.3 ft), on the island of Santa Maria, in the Portuguese archipelago of the Azores.

[2][3] Remnants of these pillow lavas can be identified 180 metres (590 ft) above sea level, helping to increase the size of the island to roughly its current dimensions.

Following a long period of volcanic activity, conditions changed, allowing the deposition of sediments and formation of beaches.

[3] The inferior layer developed in the area of the central sierra and contributed to the growth of the eastern part of the island.

[3] The periods of sub-aerial activity resulted in extensive outcroppings, lava fields, layered pyroclasts, dykes and numerous seams (approximately 230), that originated in the central relief of Cavacas until Caldeira, and passing through Pico Alto, while submarine lava flows extended into the sea in the Bay of São Lourenço, Maia and Ponta do Castelo.

[2] The first constituted exclusively by alluvium deposits and surface runoff, including lahars, in the form of conglomerates and loamy coarse particulates, such as those in Bom Despacho Velho and Alto do Poente, as well as between Feteiras and Poço Grande.