Thames

The Thames, officially the River Thames, is a major river in southern England. It rises at Thames Head in Gloucestershire, near Kemble, and flows generally eastward for about 346 kilometers (215 miles) to the North Sea. It is the longest river entirely in England and a defining waterway for London and the counties it traverses.

Course and geography: The river passes through Oxford (where it is known locally as the Isis), Reading, Henley-on-Thames, Windsor, and London, finally entering the North Sea via the Thames Estuary. Its lower reaches are tidal up to Teddington Lock, near London, about 60 miles from the sea.

Navigation and infrastructure: The Thames has a long history of navigation and today supports commercial and recreational traffic. The Port of London Authority regulates shipping on the estuary, while a system of locks and weirs manages water levels. The Thames Barrier, opened in 1984, protects central London from tidal flooding during storms.

Economic and cultural role: The river has facilitated trade since Roman times and remains important for transport, water supply, tourism, and sport. Notable events include the Henley Royal Regatta and the University Boat Race. Numerous bridges, such as Westminster, London, and Tower Bridges, connect communities along its banks.

Environment and catchment: The Thames basin covers roughly 16,000 square kilometers (about 6,000 square miles), draining much of southern England into the North Sea. Efforts to improve water quality and biodiversity have been ongoing since the 19th century, balancing urban needs with ecological restoration.