The River Stort is a river in Essex and Hertfordshire, England. It is 24 miles (38 km) long and flows from just south of the village of Langley to the River Lea at Hoddesdon. Unusually, the town of Bishop's Stortford does not derive its name from the River Stort, but the other way around. 16th-century cartographers Saxton & Camden named the river Stort, assuming the town of Stortford was named for its ford.
The river was originally a winding shallow book called the Stour. In the 17th century map makers decided to tidy things up and rename the river on the maps as the Stort to fit with the name of its principal town.