Welcome summer with a 1.5-mile hike on the longest day of the year. Discover twilight wildlife activity and hear solstice stories from around the world. This program is for adults and families with children ages 6 and older. Registration for most programs begins on the 20th of the month before the event. Registration required. Register Registration is required through Discover Boulder County, Parks & Open Space’s volunteer and event registration system. If you’re new to the system, you'll need to create an account. But it’s easy and we only use your contact information to communicate about events you register for. We will never sell or give your information to a third party.