The Posof-Akhaltsikhe border crossing connects Georgia and Turkey in the countryside. It is 10 km from Posof in Turkey, and 10 kilometres from Akhaltsikhe in Georgia. Walking across this border is allowed.
The road on the Turkish side goes over a huge mountain pass from Posof to the village of Turkgozu by the border. There is a regular flow of traffic out in either direction.
Both roads are in fine condition. Just walk an hundred metres from the border buildings and you'll easily find a good spot to catch a ride.