Altares is located along the northern flanks of the "Serra de Santa Bárbara" massif, extending from the northern and western edges of the caldera of Santa Barbara volcano to the seaside cliffs on the north coast of the island. Topographically, the civil parish is bounded on the east by the course of the "Ribeira do Pamplona" ("Pamplona Ravine"), which also serves as the border to the municipality of Angra do Heroísmo, and on the west by a line drawn from the summit of "Pico Rachado" to the sea. This line follows the course of the "Ribeira dos Gatos" ("Ravine of the Cats"), but then it diverts to the west to include the hamlet of "Cerro da Ribeira dos Gatos", a ridge of hills and miscellaneous buildings.