Gerard Mercator’s edition of Ptolemy’s ‘Geography’ is highly acclaimed; he spent much of his life studying the work and even engraved the plates himself. The ‘Geographia’ is the earliest surviving geographical treatise. Much of Mercator’s efforts were spent projecting Ptolemy’s geography onto the projection which bears his name. Mercator is one of the world’s greatest cartographers and the ‘Claudii Ptolemaei Tabulae Geographicae Orbis Terrarum’ was first published in 1578. This fine example is of Ptolemy’s central Asia and displays the Caspian Sea to the west. It focuses on the extremely important Silk Road, the famous route to the east that Marco Polo undertook. This was the traditional trading route between the Mediterranean and Asia. This region today encompasses Kazakhstan, Uzbekistan, Turkmenistan, Tajikistan and Kyrgyzstan. It is in the third state with the addition of a latitude and longitude grid illustrating the projection. Koeman Me 5; Nordenskiold 234; Phillips, P.L. (Atlases) 384; Shirley BL T.Ptol-11a & 11k; Van der Krogt, P. (Atlantes) 0927:1.1.