Esrum Å is the principal drainage of Lake Esrum, Denmark's second largest lake, located in Gribskov Municipality, some 50 km north of Copenhagen, Denmark. The 10-km-long stream extends from the northwestern part of the lake and flows past and Esrum Abbey on its way to The Kattegat at Dronningmølle. Esrum Canal (Danish: Esrum Kanal) was built in about 1800 to facilitate the transportation of firewood from Gribskov to Copenhagen, offering a navigable alternative to the upper part of Rsrum Å. It remained in use until the 1870s but has now dried out.