Let me start by saying this is the biggest museum dedicated to World War 2 that I have ever seen. The amount of vehicles and history exhibits is huge. Oorlogsmuseum Overloon is between 1 and 1.5 hours away, depending on where you live around GK.
Overloon was the site of a major tank battle between the American and German troops in October 1944, which destroyed most of the town. The museum was originally set up to educate about the history of the battle, but has expanded to show the entire history of World War 2 from the Dutch perspective. Almost everything in the museum has an English explanation, though there are a few signs here and there only in Dutch and German. The museum also has a huge collection of both Allied and German vehicles, many of which were used at the Battle of Overloon.
The museum also hosts several events throughout the year, including Militracks in May and the Santa Fe event in June (In 2015 June 20 and 21). Militracks gives you the chance to ride in vehicles used in World War 2 for between 5 and 20 euro per ride. Jeeps, motorcycles, tanks and many other vehicles ride around the museum grounds on an exciting and bumpy route. The Santa Fe event will show what life was like behind the front lines. There will also be vehicles to ride in at this event and demonstrations of the Battle of Overloon.
Museumpark 1, Overloon NL
Adults: 15 euro
Children (4-12 years old): 9 euro
3 and younger: Free
Museum Card Holders: Free