However, for the greater part of the last millennium, Phuket was known as Junk Ceylon, which, with variations, is the name found on most old maps. The name is thought to have its roots in Ptolemy's Geographia, written by the Alexandrian geographer in the 3rd century AD. He mentioned that in making a trip from Souwannapum to the Malay Peninsula, it was neccesary to pass the cape of Jang Si Lang.