The Mother See of Holy Etchmiadzin is the heart of the Armenian people's spiritual life and the residence of the Catholicos of All Armenians. It is one of the world's oldest Christian cathedrals founded in the early 4th century based on the vision of Saint Gregory the Illuminator. According to tradition the Only Begotten Son of God descended from heaven and pointed to the site of the cathedral with a golden hammer giving rise to the name "Etchmiadzin" (The Descent of the Onl