Memorial Museum Passchendaele 1917 is a museum that gives Ypres visitors another angle on the place, especially if you have already covered the obvious landmarks. It is the kind of stop that works best when you are building a slower day around a neighbourhood, a park, or a cluster of nearby sights rather than racing through a checklist.
Go for the collection and for the local context it adds: smaller museums and galleries often explain a city better than another grand square. Check current opening hours before crossing town, then give yourself enough time to read the labels and notice how the building sits in its surroundings.