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 University merger with Teesside College of Education took place in the 1970s along with the purchase of Flatts Lane. The Clarendon Building was added in 1973, as was the Stephenson Building in 1976. Both of these buildings remained in use for the Polytechnic's long-awaited conversion into a university. That happened on 16 June 1992, when Teesside Polytechnic became the University of Teesside, one of the UK's first new universities following that year's Further and Higher Education Act. By the 1990s, the institution had almost 8,000 students. In 1997 the old Polytechnic's library was replaced with a Learning Resource Centre. Subsequent additions