The Soot Canal, constructed in 1849, has Norway's oldest sluice gates. It was the work of Engebret Soot (1786-1859). It was built to allow timber to be transported (floated) to the Halden sawmills. The canal was 1.5 km long and had 16 locks which extended from Lake Skjervangen at 185 m above sea level up to Lake Mortsjølungen at 201 m above sea level. Grasmobanen is part of the canalsystem.