This early European world map is called a “T–O Map” because of its symbolic design. Originally drawn in the seventh century as an illustration for an encyclopedia of world knowledge by Isidore of Seville, the design had great religious significance. The “T” represented a Christian cross that placed Jerusalem at the center of the world. It also separated the known continents—Asia, Europe, and Africa. The “O” enclosing the entire image represented the medieval idea of the world surrounded by water.