A mill race, raceway or mill lade (in Scotland) is the current or channel of a stream, especially one for conducting water to or from a water wheel or other device for utilizing its energy. The race leading to the water wheel is called the head race, and the race leading away from the wheel is called the tail race.
Hikers on the Ben Utter Trail in Arcadia State Park, Hope Valley, Rhode Island, can see the site of a former sawmill and may notice man-made channels cut into the granite. These grooves formed the millrace, increasing the speed of the water as it approached the sawmill so that it would have adequate force to turn the mill's huge waterwheel.
Mill Race was also the name of a test of nuclear technology using 620 tons of conventional explosives, conducted in 1981 at the White Sands Missile Range.
Besides Scotland, certain races in England, such as ones in Godmanchester, Cambridgeshire and Nayland, Suffolk are called "mill lade".