Teesside Teesside Teesside () is the conurbation in the north east of England around the urban centre of Middlesbrough that is primarily made up of the towns Billingham, Redcar, Stockton-on-Tees, Thornaby and surrounding settlements near the River Tees. It was the name of a local government district between 1968 and 1974—the County Borough of Teesside. Teesside remains an important centre for heavy industry, although the number of people employed has declined. Traditional industries, primarily steelmaking (British Steel) and chemical manufacture (Imperial Chemical Industries (ICI)), have been replaced to a large extent by high technology activities, science development and service sector roles.
County Borough of Teesside County Borough of Teesside Teesside was, from 1968 to 1974, a local government district in northern England. It comprised a conurbation that spanned both sides of the River Tees from which it took its name. The district had the status of a county borough and so was independent of the County Councils of the North Riding of Yorkshire and of County Durham, in which it was geographically located. The River Tees formed the historic county boundary between Yorkshire and Durham. A continuous conurbation had built up around the mouth of the river, increasing greatly in population from the nineteenth century