A free museum in an area densely populated with other museums, gardens and memorials in Parc du Cinquantenaire. It's an easy 10 minute or so Metro ride from Brussels Central to Merode station. Please check opening times as currently it does not open on Mondays and shuts for lunch on the days it is open.
In one huge hall there is a large collection of military aircraft illustrating the development of the Belgian Air Force from its inception to almost the present day: from WW1 to an F-16. Many of which are of British origin, (including 2 Spitfires and a Hurricane), until the waning of the British aircraft industry and the switch to sourcing from the US post-Hawker Hunter.
In other halls, there is a huge array of weapons, guns, tanks and uniforms charting the history of the development of modern land warfare in Europe, with some fascinating detail of the Napoleonic battles and of course, the trench warfare of WW1 along with Belgium's involvement in conflicts overseas.
Only criticism is that the exhibits do not have the same level of explanations in English as they do in the local languages but there is are guided tours available in English if you have the time.
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