In Denver for work. Staying downtown by convention center. Recommendation for where to swim?
The Denver Athletic Club has a nice indoor lap pool. I do not know if they allow day passes. If you can make the short drive to Denver University, it has a great aquatics center and a very good masters program.
Carla Madison rec center is great. $6 day pass.
The 20th St Indoor pool is 4 lanesx20 yards and while not fancy, is rarely used and very close to the convention center.
any year-round outdoor pools in downtown Denver?
I believe the closest is the Cherry Creek Athletic Club in Cherry Creek, about 4-5 miles from downtown. And they have a temp cutoff of an expected high temp of 34 to be open.