The Sulu Archipelago is a chain of islands in the Pacific Ocean, in the southwestern Philippines. The archipelago forms the northern limit of the Celebes Sea and southern limit of the Sulu Sea. The Sulu Archipelago islands are within the Mindanao island group, consisting of the Philippines provinces of Basilan, Sulu, and Tawi-Tawi; hence the archipelago is …The Sulu Archipelago is a chain of islands in the Pacific Ocean, in the southwestern Philippines. The archipelago forms the northern limit of the Celebes Sea and southern limit of the Sulu Sea. The Sulu Archipelago islands are within the Mindanao island group, consisting of the Philippines provinces of Basilan, Sulu, and Tawi-Tawi; hence the archipelago is sometimes referred to as Basulta, derived from the first syllables of the three provinces.