Even if T=O maps can be found as early as the 7th century in Isidore of Seville’s Encyclopedia, Medieval Europe has many examples of maps that appropriated the circular form both as a representational resource and as a vehicle to express symbolism. In the case of the T=O map, the truncated cross within the disc, the world was depicted as a circle with a T within, the upper half representing Asia, the lower left Europe, and the lower right Africa. Jerusalem defines the center (in the time of the crusaders, Jerusalem often appeared as a complete circle divided into quadrants). The T=O map in the image was printed in Augsburg in 1472. The vertical segment of the T is the Mediterranean sea (Mediterraneum), separating Europe from Africa. Asia is separated from Europe and Africa by an unknown Maremagnum Fine, and circling all three continents, the outer ring of the circle is the Mare Oceanum, the outer limit of the Earth as it was understood then. The circle as a cartographic instrument was never as powerful as it is in this map, which possesses an extraordinary symbolism that could only be embodied in the circle, the most symbolic of all geometric forms since the beginning of times.
