Chibbyr Ulf (Sudric for Ulf's Well) is a lake just north of Ulfstead, and the start of the Ulfstead River. The name derives from Ulf, a lieutenant of Thorkell of Norwich. Ulf was a jovial man with a perpetual thirst. His thirst was really for ale; but his men, in jest, called the lake Chybbyr Ulf - Ulf's Well - and the name stuck. At some point, the waters of the lake was harnessed to power the wool mills of Ulfstead. In recent times, electricity has replaced water power.