Magellan didn't go to Limasawa. Or Butuan. The place where Magellan’s fleet anchored and where an Easter mass was celebrated on March 31, 1521 was not Butuan. Or, Limasawa. It was in the island-port named Mazaua. Being an island, it was surrounded by sea water. There is an article at Wikipedia on Mazaua where all the properties of Mazaua–its location, size, kind of port, shape, the name of its king, its flora and fauna, distances from Homonhon to the port, latitude, etc. etc.–are explicitly defined.
A fairly comprehensive but not exhaustive historiography of the Mazaua issue is contained in an article published in the website of the Italian nuclear scientist and Italian translator of Dr. Jose Rizal, Dr. Vasco Caini. When the page opens scroll down to the article Mazaua. The notion the March 31, 1521 mass was held at Butuan comes from the garbled account by Giovanni - by Vic de Jesus