A brevet is a predetermined route that needs to be completed within a certain time limit, typically on a bike. The routes are approved by RUSA (Randonneurs USA) or in Canada by Randonneurs Canada. Along the route, at strategic points, are controls with their own time limit. Note, you can also be too early and will have to wait. At these controls you need to get your brevet card time-stamped and initialed as prove you made it.
This was my first year racing Purgatory, so although I was lacking a bit of course knowledge I did come in with some pretty good fitness. The course has two main distinguishing features—the 1 km climb up Lackey road followed by the open (to the wind) and straight false flat finish; and a 2.5 mile twisty descent on the back side, followed by some more rollers.