Old Fort Number 4 is a neat place to visit. There is a lot to see around the fort inside and out. They have displays of a birch bark home and canoe, and a dugout canoe. They also have an earthen oven, cannons, and weaving equipment on site. There is a gift shop and sometimes they have living history interpreters on site to answer questions.
This fort has stairs to go up to the upper level, and there is walking involved but the site is fairly compact. This is their website: http://fortat4.org/ They have living history events, but we have not been there during one of the events.