 He was gifted land by the rulers of Canara, on which he built the Milagres Church, Mangalore, Karnataka.Completed in 1680, this church is a prominent place of worship for Mangalorean Catholics.Bishop de Castro died in Mangalore on 16 July 1684 at the age of 68 years, his grave in the Milagres Church cemetery can be identified by a bronze slab next to the St. Monica Chapel.