It is hard not to say a lot of great things about the Storm Mountain Day Use Area. It is located only a few miles up the canyon, but still makes you feel like you are far into the mountains. There are many great things to do here, but unfortunately overnight camping is not one of them. Fishing in Big Cottonwood Creek is popular, and there is terrific rock climbing in almost all directions (visitors can literally find dozens of routes). There is a short hike with great views up and down canyon. Day use facilities include six group picnic sites that are available for reservation and several smaller sites that are available on a first-come, first-served basis; families will also find a playground for children, so there is no reason not to head a short way up the canyon to have dinner with the family outdoors.
Note that you must bring your own drinking water to Storm Mountain Day Use Area, but restrooms are available. Also, because this is a watershed area, dogs won't be able to join you on this adventure.