Teesside Steelworks South Bank coke ovens and the BOS plant at Lackenby closed in 2015. The Teesside Beam Mill and some support services still operate at the Lackenby part of the site. Steel production on Teesside begins when Bolckow, Vaughan & Co Ltd, formerly Bolckow, Vaughan, opens the Cleveland Steelworks in Middlesbrough. Using the Bessemer process, the works have 3 blast furnaces. Albert John Dorman enters into a partnership with Albert de Lande Long taking over the West Marsh Ironworks in Middlesbrough. Dorman Long is founded. Bolckow, Vaughan & Co Ltd. acquire the Southbank Steelworks. The firm is also persuaded by Sydney
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