In Anatolia, at the beginning of the 2nd millennium BC, in the archives of Salim-Assur son of Issu-Arik, found at Kanesh, Assur-Tab, son of Azuzaya, went to Salahsuwa where he sent a man named Adada negotiates at Kussara an agreement to be able to transit goods via the narrow track or the «Sukinnu Route». He failed and was later caught in the narrow track.
Kussar was the main political city of the Anatolian peninsula. It is normal that there were agreements between the merchants and the local kings. Kussar is best known in the texts of Hattusa as being the city of the ancestors of the Great Kings of Hatti who were Pithana and his son Anitta. These kings of Kussar have conquered Kanesh and thus formed the outline of what will be called the Hatti or the land of the Hittites. In doing so, they decreased the trade relations with Assyria. But perhaps the town have declined consecutively of the abandon of the transit through Kanesh.
The site of Kusura Höyük near Afyon Karahisar, was excavated by Winifred Lamb of the University of Cambridge, from 1935 to 1937. The main archaeological layers have been identified of the Chalcolithic and the Early Bronze Age until the beginning of the trade of the Kanesh merchants. The site is famous because of the discovery of female idols which are called Kusura-Beycesultan.
It is an argument which justifies the hypothesis proposed by this blog for the "Sukinnu Route".
My notes of veracity :
4000 years ago, the site of Kusura Höyük as the town of Kussara: 3/5