The Great Ouse is a major river in England, flowing through the counties of Bedfordshire, Cambridgeshire, and Norfolk. It stretches approximately 143 miles (230 kilometers) from its source near Brackley in Northamptonshire to its mouth at King's Lynn in Norfolk. The river is known for its scenic landscapes and is a popular destination for boating and fishing. Historically, the Great Ouse has played an important role in trade and transportation. It was navigable for much of its length, allowing goods to be transported between inland towns and coastal ports. The river is also home to various wildlife, making it an important ecological habitat.