When Europeans first arrived on Guam, Chamorro society had three classes:matua (upper class), achaot (middle class), and mana'chang (lower class). The matua were located in the coastal villages, which meant they had the best access to fishing grounds whereas the mana'chang were located in the interior of the island. Matua and mana'chang rarely communicated with each other, and matua often used achaot as an intermediary. There were also "makåhna" (similar to shamans), skilled in healing and medicine. Belief in spirits of ancient Chamorros called Taotao mo'na still persists as a remnant of pre-European society. When Magellan arrived on Guam, he was greeted by hundreds of small outrigger canoes that appeared to be flying over the water, due to their considerable speed. These outrigger canoes were called Proas, and resulted in Magellan naming Guam Islas de las Velas Latinas (Islands of the Lateen Sails).Guam—the only Spanish outpost in the Pacific Ocean east of the Philippines, became the regular port between Acapulco, Mexico and Manila from 1565 to 1815, and (since Philippine independence) the most western outpost of actual United States territory in the Pacific—is the biggest single segment of Micronesia, the largest islands between the islands of Kyushu (Japan), New Guinea, and the Philippines, and the Hawaiian Islands.