White River State Park is the area with several museums. There is a canal running inside the park. You can rent a bicycle there. I have seen some families riding multi-people cylces (?), so I think they also rent more than bicycles. If you prefer water, you can rent a boat and enjoy riding it, or you can ride gondolas. Just taking a walk along canal is very relaxing. If you have small children, make sure they don't get too close to the canal! There is no protective fence or anything between water and sidewalk.
I highly recommend visitng this area with your loved ones and enjoy being outside. Also, it's great place to go see 4th of July fireworks. This year, they had food venders set up at the park. I have not yet tried to go see Labor Day's fireworks at White River State Park, so I don't know if you can get a good view of fireworks.