Pay attention to the opening and closing times of the castle (e.g. until 6 p.m. in summer). Then the access to the garden and keep will be closed. Otherwise, parts of the facility can then be explored free of charge.
Part of the castle is open to the public until 6 p.m. during the day, except for the youth hostel building. The tower looks very well maintained. You have a beautiful view of the Kinzig valley, Offenburg and the Rhine plain.