|Length||23.4 mi (37.7 km)|
Its northern terminus is a roundabout with the A487 trunk road between Llanwnda and Llandwrog ( It then runs south-westerly along the northern coast of the peninsula, through ).Clynnog Fawr then turns inland crossing the peninsula to meet the southern coast at Pwllheli, it then follows that southern coast to terminate at Abersoch ( ).
Work started in February 2008 to upgrade the road between Aberdesach and Llanaelhaearn and also bypass Clynnog Fawr. This work is expected to complete in Summer 2009. Previous work in 2006/2007 had cleared the new route of trees and erected boundary fencing.