The River Lea just outside of Ware and looking towards Hertford. The building in front is the Gauge House that could take water from the River Lea and divert it into the 'New River'. The New River was constructed as a canal to supply North London with drinking water, and its main sources are an aquifer at Chadwell Springs and from the other side of the town of Ware at Amwell springs. The artificial waterway has supplied water to London for 400 years.