The Churún River (Spanish: Río Churún) is a river in Venezuela, part of the Orinoco River basin. It is located around6.0666667°N 62.6°W, in Canaima National Park and a tributary comes from the Angel Falls, which are the world's tallest single-drop waterfall.

The River Churn famously rises at Seven Springs in Gloucestershire, located just south of Cheltenham in the Cotswolds. This site is marked by a set of springs where water bubbles out of the limestone at an elevation of about 200 meters. Interestingly, because Seven Springs is further from the sea than the traditional source of the Thames (Thames Head), many locals and geographers argue that the Churn is the "true" source of the River Thames. The river flows roughly 37 km (23 miles) south, passing through North Cerney and Cirencester, eventually joining the Thames at Cricklade. While the Churn is technically a tributary, its consistent flow from these springs makes it the primary hydrological contributor to the young Thames, maintaining a vital role in the water cycle of the central English landscape.