This is a beautiful piece of interactive art in downtown Nederland, right next to an amazing coffee and donut shop.
This hike is particularly beautiful this time of year, we cannot recommend it highly enough (but be sure to get there early, parking is fraught!)
There is hiking, fishing, and picnicking galore to be had at this beautiful spot. Admission is free with a national parks pass!
There is so much to do in Boulder that it's really an embarrassment of riches. Many of those things can be found on Pearl Street, right on the other side of the canyon.