One of the most beautiful old churches, both inside and out, is a 30 - 40 minute drive out of Boulder between Lyons and Estes Park off of Highway 7. It is St. Malo located near the Longs Peak Trail head access road. You can see the church from the highway, it is a stone building with stained glass windows that overlooks a trout stream / pond ( decent flyfishing for small brookies ). The drive up is fantastic and the mountain views are spectacular. There are some excellent hiking trails that can be accessed from the St. Malo property as well. It's worth the drive. Very popular wedding location as well.