Depending how where you are thinking of going and what your vehicle situation is, Alta, Colorado (ghost town) and Alta Lake are just south of Telluride. Bit of a off road drive to the top, but Alta Lake is amazing. Sure there are "closer to Denver" options, but Telluride is a great mountain city and Alta has disbursed options. You can tent camp right on the lake. At least when I was there last you could.
Leadville is a cool little town, has Camp Hale (WW2 base we trained the ski troops to prep for Alpine warfare) is just north for exploration. Lots of hiking in that area as well.
Both are a bit off the map compared to the standard tourist areas.