Hōlei Sea Arch is a 90-foot-high natural arch located in Hawaii, on the southern coast of the Big Island, south of Kīlauea. This rock formation was born from marine erosion, in which the waves of the Pacific Ocean create this natural bridge of lava cliffs. The arch is made of basalt. It takes its name from the Hōlei Pali, the escarpment located up on the slopes of the volcano.