The 7 Natural Wonders of Boulder

The Flatirons — those massive, slanting red rock formations that were deposited 300 million years ago and uplifted about 220 million years after — are Boulder’s calling card and are an obvious must-see on your visit. But with 46,000 acres of open space in our city, you might be surprised there are even more geologic curiosities and nature-made marvels tucked into every corner of Boulder’s wild landscape. We’ve compiled the top seven natural wonders so you can lace up your hiking boots, get your camera ready and consider this a checklist for outdoor adventure.

Help protect Boulder's natural beauty by remembering these Leave No Trace principles whenever you're spending time in the great outdoors.