Teesside is a built-up area around the River Tees in northern England, split between County Durham and North Yorkshire. The area contains the towns of Middlesbrough, Stockton-on-Tees, Billingham, Redcar, Thornaby-on-Tees, and Ingleby Barwick. Teesside's economy was once dominated by heavy manufacturing until deindustrialisation in the latter half of the 20th century. Chemical production continues to contribute significantly to Teesside's economy.
