Go and see the famous concert venue! There are many hikes around the venue additionally. Find on Google or the app Alltrails.
A bit far, but if you are coming early or staying late it's a beautiful area to walk or hike around.
There is an outlet mall in Castle Rock, Cherry Creek Mall in Denver, and South Broadway has many thrift stores and fun shops.
Easy hike in Littleton, 2.6 miles round trip, There is a small fee to park at the base of the hike.
3 mile hike in Red Rocks, with about 400 feet of elevation gain. Find online or on Alltrails!
Downtown Littleton is about 15 minutes from the venue! There are many boutiques and restaurants. Perfect for breakfast or lunch before the wedding.