Ypres, also called Ieper, depending if you're speaking French or Dutch (Ypres is what us Brits call it). It also has an excellent museum, whose excellence I cannot emphasise enough. Ypres also has the Menin Gate, as well as numerous war cemetaries scattered within and without the town.

If you visit Ypres, you can pay your respects by attending the Last Post at the Menin Gate at 8pm sharp.

There is also the Salient Museum, and Sanctuary Wood Museum. There's also a museum in Passchendaele.

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