It's a navigational rally, until he was given the locations of the waypoints at the start of the rally this morning even Boyd didn't know what his route will be... he may still be making it up as he goes!

As I understand it the competitors are given, at the start of the 36 hour period, a list of locations and how many points it's worth to visit each location. It is impossible to visit all the locations in the time allowed. They then choose which locations to visit, they must complete at least 1,000 miles and return to the start point within the time limit and the object is to attain as high a score as possible.
Hopefully that's all correct, feel free to add if I missed anything/got anything wrong?