Patmos is a small Greek island in the Aegean Sea, most famous for being the location of both the vision of and the writing of the Christian Bible's Book of Revelation.  Because of the Book of Revelation, Patmos has a long history as a destination for Christian pilgrimage. Visitors can see the cave where John is said to have received his Revelation (the Cave of the Apocalypse), and several monasteries on the island are dedicated to Saint John.

In 1999, the island's historic center Chora, along with the Monastery of Saint John the Theologian and the Cave of the Apocalypse, were declared World Heritage Sites by UNESCO. The monastery was founded by Saint Christodulos. Patmos is also home to the Patmian School, a notable Greek seminary.