An 11th Century castle along the Rhine, Sooneck is available to view only via a guided tour. However, if you’re touring many castles and just want to get a glimpse, admission to the grounds is also available, where you can get a peek at the castle, roam its gardens and enjoy a snack in the castle’s cafe, which overlooks the river. The castle is open April through September every day but Monday from 9 a.m. to 6 p.m. and then closes earlier in the winter months.