Did this race in '21, and like the previous poster, I have a love/hate relationship with this course.
Race kit pick up and transition area are great. I didn’t find it overly busy (mind you it was still during covid). Only issue here is parking to get to Summit place. Sometimes this can be a trek, but it is like that at almost all IM events.
I actually had one of my best swims here and thought it was faster than most. You swim out into the lake, do a counterclockwise look and then head back down through the river. Run into T1 is about 200-300m if memory serves me right. Mounting your bike is an issue. The mount line is right on a hill getting out of the parking lot, so be sure to be in your easiest gear. Wife said she saw at least a dozen people fall here.
Onto the bike, it was very rolling. I would say some of the hills are actually good climbs, but I come from absolutely flat SW Ontario, so an overpass is a hill for me. About 30km into my bike in '21 there was a severe thunderstorm and torrential downpour, so I honestly was just trying to survive for about 40km until it stopped. I do remember hitting 75 km/h on a downhill though lol. I’ll never forget that. Overall, it’s a solid, honest bike course.
The run for me was horrible. Again, you start coming out of T2 parking lot running up hills to get to the meat and potatoes of the course. Crowd support was pretty good for about 85% of the route they chose that year, so that was good. It just seemed like you were constantly running up hill lol. If you can deal with that, you’ll be fine.
Weather should be decent, but in '21 after that storm, it got stupid humid, which added to the difficulty of the run. I didn’t check, but if it’s still in July, you can expect a decent temp anywhere around 26C-32C. Outside of that would be abnormal. Mornings can be cold and foggy as well, depending on the week leading up to the race.
Overall, Muskoka is a solid, honest, well-run event. I won’t do it again based on the hills and I also want to try different events but would highly recommend to others. It’s a challenge, and that’s what we all want.
Get there early on race day as parking can be an issue. Lots of road closures in the area as well, so be prepared to delay your exit after the race or park accordingly.
Good luck.
Cheers
Quinner