The Fountain of Life, or in its earlier form the Fountain of Living Waters, is a Christian iconography symbol associated with baptism, first appearing in the 5th century in illuminated manuscripts and later in other art forms such as panel paintings. The symbol is usually shown as a fountain enclosed in a hexagonal structure capped by a rounded dome and supported by eight columns. The fountain of living waters, fons vivus is a baptismal font (a water fountain in which one is baptized, and thus reborn with Christ), and is often surrounded by animals associated with Baptism such as the hart. The font probably represents the octagonal Lateran Baptistery in Rome, consecrated by Pope Sixtus III (432-440), which was iconographically associated with the fountain of the water of life mentioned in Revelation 21.6.