We haven't been to the parks in 5 years, and never carried a backpack before. this time, with 4yo DS & his stuff, plus my dslr camera & supplies, and snacks I am planning on bringing a largish backpack. Do they have bins for bags? do you try to maneuver it onto the ride with you? We will have an umbrella stroller but I don't really feel comfortable leaving my camera hanging on it while we ride.