18300 W. Alameda Pkwy., Golden
This natural amphitheater is surrounded by dramatic red rocks that, in addition to being stunningly beautiful, reflect sound back onto the stage, giving it the best acoustics of any outdoor arena in the states. Red Rocks is famously a bucket list venue for many performers, so the lineup is a little of everything—everyone from The Beatles to Daft Punk to the Grateful Dead—and, for a few nights in the summer, the Colorado Symphony—has played the stage. Arrive early so you can tailgate in the parking lot and admire the sunset, then head into the venue where you'll be able to see every single star above the performers' lights. If you can't catch a concert, it's worth stopping by during the day to admire the rocks—you'll find plenty of locals here around sunrise running the stairs.
910 Jackson St., Golden
Outward Bound is an organization that values learning by doing. Its reach and range of classes and expeditions is extensive—in the US alone (it's an international network), about 35,000 students are enrolled in programs each year, whether classroom- or wilderness-based. The expeditions are for middle school, high school, and college students; adults; and families. The classic Outward Bound wilderness expedition lasts for fifteen days and brings students out into the wild where they partake in any number of exciting (yet challenging) activities from canyoneering to rock climbing, dog sledding, and river rafting. The trip locations are varied: Alaska, Appalachian Mountains, Outer Banks, Colorado Rockies, and so on. It's another summer experience that sticks.