Teesside the four independent unitary authority boroughs of Hartlepool, Stockton, Middlesbrough and Redcar and Cleveland (a renamed Langbaurgh). At this time they were returned to the counties of North Yorkshire and County Durham for ceremonial purposes, with Stockton-on-Tees becoming the only district in England split between two ceremonial counties. In 1998 the neighbouring Borough of Darlington also became an independent unitary authority and this along with the four former Cleveland boroughs form the sub-region of the Tees Valley which is used for statistical purposes and governmental organisation. The name Tees Valley is increasingly promoted for economic and cultural connections, though Teesside,
Teesside of approximately 492,954 people. Teesside industry is dominated by the commodity and in many instances, integrated chemical producers of the Northeast of England Process Industry Cluster (NEPIC). These companies are based on three large chemical sites around the mouth of the River Tees at Wilton, Billingham and Seal Sands. These companies make products such as petrochemicals, commodity chemicals, fertilizers and polymers. Teesport is based on the River Tees and is currently the third largest port in the United Kingdom, and amongst the ten biggest in Western Europe. This port handles over 56 million tonnes of goods per annum which are