Saint John grew up in the Desert because when King Herod was killing the Holy Innocents, all the baby boys in an attempt to kill the new born Baby Jesus, Saint Elizabeth fled to a rocky and desolate place with Saint John in her arms. When Saint Elizabeth saw the soldiers following her she cried out to the mountain: “O Mountain of God, receive a mother with her child!” and the rock opened and hid the mother and child. The soldiers killed Prophet Zacharias in the Temple when he refused to say where his child went, and forty days afterwards Saint Elizabeth reposed. Saint John was then led to the wilderness by an Angel where he grew up protected by God, he was one and a half years old.
Below is a photo of the Holy Tomb of Saint Elizabeth.