Yarm, also referred to as Yarm-on-Tees, is a market town and civil parish in the Borough of Stockton-on-Tees, North Yorkshire, England. It is i…Yarm, also referred to as Yarm-on-Tees, is a market town and civil parish in the Borough of Stockton-on-Tees, North Yorkshire, England. It is in Teesdale with a town centre on a small meander of the River Tees. To the south-east, it extends to the River Leven, to the south it extends into the Kirklevington.