The tallest peak of Haleakalā (house of the sun), at , is Puʻu ʻUlaʻula (Red Hill). From the summit one looks down into a massive depression some 11.25 km (7 mi) across, 3.2 km (2 mi) wide, and nearly 800 m (2,600 ft) deep. The surrounding walls are steep and the interior mostly barren-looking with a scattering of volcanic cones.