Thornaby-on-Tees, commonly referred to as Thornaby, is a town and civil parish on the River Tees's southern bank. It is in the Borough of Stockton-on-Tees, North Yorkshire, England. The parish had a population of 24,741 at the 2011 census, in the Teesside built-up area. The town had a royal charter enacted to form a municipal borough in 1892, during the Victorian era, before merging into the County Borough of Teesside in 1968. A borough no longer defines a specific settlement's status as a town in England since the Local Government Act 1972 reforms. The modern centre was built on the north eastern part of Thornaby airfield and lies 2 miles (3.2 km) south-west of Stockton-on-Tees and 4 miles (6.4 km) south-west of Middlesbrough. From Wikipedia