Kosh is a village in the Ashtarak Municipality of the Aragatsotn Province of Armenia, 18 km south-west of the district centre Ashtarak. The town is attested as Kvash in early Christian times. In the town are ruins of a 13th-century church - Saint Grigor - and a castle which has yielded Hellenistic pottery remains. There are numerous remains from early Iron Age residential ruins and buildings of large basalt stone blocks.