Hi John, There were actually many races in the 60's. Sled dog racing in New England was practically at its peak at this time, but you are in luck because I know this race extremely well!
The race documented in this film is the World Championship Sled Dog Derby in Laconia, NH. Back in the 60's the mileage was a lot higher and the drivers would begin in Downtown Laconia and go through many other towns including Belmont and Meredith. Obviously today we can't do that because of the development. The Lakes Region Sled Dog Club runs the race but as you see on the vehicle "New England Sled Dog Club," they often helped with the timing of the races.
In some of the shots it shows downtown Laconia with the Colonial Movie theater and Sawyers Jewelers. Then some roads in the Laconia area.