Angra occupies the south coast of Terceira. It is the headquarters of a military command and the seat of a Roman Catholic bishopric. Its principal buildings are the Sé Cathedral of Angra do Heroísmo, a military college, an arsenal, and an observatory. The harbor, now of little commercial or strategic importance (but formerly a major commercial and military port), is sheltered on the west and southwest by the promontory of Monte Brasil, but, today, it is less important than the neighboring ports of Ponta Delgada on the island of São Miguel and Horta on the island of Faial.