unlike previous LO300/600 Challenges the 2021 course lies entirely in Canadian waters with US waters to be treated as an obstacle. For related safety reasons rounding of Main Duck and Yorkshire Islands have been removed and M9 is the mark to be rounded at the east end of the lake.
Main Duck Island Course is a approximately 300-nautical mile course on Lake Ontario, starting at Port Credit, on to the Fogh LSYC Mark, then on to M9 via the Ajax Weather Bouy, back to the west end of the lake to round Burlington Weather Tower, again via the Ajax Weather Buoy, and finally to PCYC for the Finish. Well, for the LO300 participants it the Finish, but the LO600 racers will complete a second circuit around the course omitting only the Fogh LSYC Mark for this second lap.
Scotch Bonnet Island Course is a 222 nautical mile course starting at Port Credit, then on to the Fogh LYSC Mark, Scotch Bonnet Island, the Ajax Weather Mark, Burlington Weather Tower, and then on to the PCYC Finish.
Complete details for both courses and course marks are available in the Sailing Instructions on the Yacht Scoring Registration and Race Document Web Site.