Fly'n B Park is a nice little hidden gem in Highlands Ranch. Awesome spot to walk and fish for all the blue gill fish in the pond. Just need some night crawler segments (yeah, it gets a little messy) and a bobber and in the spring and summer you can get a ton of action. I've been out there with my kids and they've each caught 20+ fish.
But this cache has nothing to do with fishing. The Fly'n B Park is a good place to start though as you take the trail south to this spot. This cache is hidden where the Fly'n B Park trail turns into the High Line Canal Trail. Should be an easy find. Keep walking for more scenic views.