What is "teesside"

Teesside is the name given to the conurbation in the north east of England around the urban centre of Middlesbrough that is also made up of the towns of Billingham, Redcar, Stockton-on-Tees, Thornaby and surrounding settlements near the River Tees. It was also 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' or 'ICI'), have been replaced to a large extent by high technology activities, science development and service sector roles.