The document analyzes primary sources related to the site of the first Catholic mass in the Philippines. It summarizes the accounts of Francisco Albo and Antonio Pigafetta, who were part of Magellan's expedition. Albo's log describes locations like Mazava that match the description of Limasawa island. Pigafetta provides more details, noting their arrival at Homonhon island on March 17, 1521, where Magellan said mass. Scholars analyzing these firsthand accounts came to question the long-held belief that the first mass was in Butuan, and suggest it actually occurred at Limasawa or Homonhon.