Lots of great suggestions.

One recommendation I didn't see is to spend 24 hours in Denver before heading up to the high country. It could prevent feeling like crap and not being able to train for a couple days, or much worse.

A big thanks to all for sharing their thoughts! I have done my own personal "training camp" inn Flagstaff over the years, and at 7k feet, I didn't feel too impacted.

tball and all (and I know this is an N=1 question), but have you found a significant difference in adaptation above 9k? Thank you again to all for the knowledge!

Chef - I'd appreciate any information you could provide. Thank you! At this point, I am thinking about a short-term rental for three weeks (late May to mid-June) and work remotely from there. It's only a two hour time difference between there and the east coast and very doable work schedule-wise. The goal is to get some low intensity/high volume training before racing in early July (the wildcard for me is whether or not Canada lifts its travel restrictions by then).

I think I have a pretty good plan put together (trails, grocery stores, swim locations, etc.) with one big exception - is there a good place to rent a bike there?

I live at 5k and have a condo at 9k. I notice the biggest difference swimming - it feels like I’m sucking air through a straw when I start- but after a few days it gets more normal.

All, thank you for all of the info last year!

I stayed in Breck for a few weeks in May/June 2021 (before Delta) and found it delightful. Found a wonderful place on the east side and did a fair bit of riding, hiking and swam at the Breckenridge Rec Center. Turned out that my July race got pushed back to October, which made it a non-starter. So I deferred. Anyway, going to try for round two. I'm interested in going back to Colorado (and maybe Breck), but asking for additional suggestions. Any towns that aren't Boulder, have a swim option, and a good trail system for MTB and trail running. Thanks all!

Ouray is, by far, my favorite place in Colorado during the summer. The Ouray hot springs has several lap lanes that are rarely used, and you can enjoy the hot springs as well, along with a great view.

Great gravel biking and a ton of hiking trails, along with quick driving to Telluride, Ridgway, and Silverton. Not sure about true MTB though. I saw a few trails on Trailforks but haven't ridden any of them.

Rent a Jeep in Ouray and go exploring through the mountains. It's stunning.

One downside is that it's a long drive to Ouray if you're flying into Denver. We have an RV so we drive. We'll be there for 2 weeks in June.

I've seen the pics and it looks like a beautiful little town, and I watched a few videos on YouTube. I had kinda come back to the idea of heading back to Breck, but my wife has mentioned Ouray (so that's where we will probably end up =)). Thanks!

If you’re willing to move a bit, Durango is a short drive from Ouray and has fantastic mountain biking. Plenty of MTB shops to rent from also. Too far for a day trip but not a far drive.