If the weather's not playing nicely, why not spend your day at Dutch Fortress Museum? You'll be fascinated by just how many interesting facts you can uncover about days gone by here.
You'll have sightseeing choices galore when in Naarden. Dutch Fortress Museum is a good place to start here, but there are plenty of other interesting sights to visit. Kunstlinie Almere Flevoland KAF, Almeerderstrand, and Muiderslot are near the collection of historical artifacts and will round out your day nicely.