The Ypres Cloth Hall was completed in 1304, one of the great civic buildings of the medieval Low Countries, an expression of the wool wealth that made Ypres briefly equal to Bruges and Ghent. German artillery began to demolish it in November 1914 and finished the job systematically over the following four years. By 1918, only fragments of wall and the lower portion of the belfry remained standing. The Allies considered leaving it as a ruin, like Coventry Cathedral was later left, but the people of Ypres voted to rebuild. Reconstruction took from 1928 to 1967. Master masons cut new stone to the original mouldings. The Names List Project, housed in the museum's research centre, is now compiling a record of every person who died in the Westhoek as a result of the war: civilian, soldier, of any nationality. The reconstructed hall is the appropriate building for that project, because it was killed and brought back too.

The microchip in the bracelet is doing something simple. As each visitor walks through the rooms in a particular order, the personal story of one of four real people surfaces at relevant moments on screens and headsets in the chosen language. A Flemish farmer's wife displaced from her village. A British medical orderly. A German soldier in a forward observation post. A Belgian child raised in occupation. The four come from the museum's research files and are based on letters, diaries and photographs. They are not composites. The choice is deliberate: in a place where 450,000 men were killed within a few hours' walk, statistics anaesthetise. The bracelet's job is to refuse that anaesthesia. You leave the museum knowing four specific people who actually lived, and were caught in this, and in three of the four cases did not survive it.

The exhibits run the breadth of the war as it touched this corner of Flanders, the Westhoek: the German invasion of August 1914, the four years of trench fighting from the beach at Nieuwpoort south to the Leie at Armentieres, the end of the war and the long aftermath. Objects do most of the work. A British stretcher, mud still in its weave. A German gas mask. A child's shoe. A mule and munitions wagon. The first chemical weapons in the history of warfare were used a few kilometres north of here on 22 April 1915. The museum displays a chlorine cylinder. The curator, Piet Chielens, is a working historian, and the labels are honest in a way that older war museums often were not. The introduction says plainly that the museum does not glorify war but suggests its futility, as seen in the West Flanders front region in World War I. Then it lets the objects say it.

On the way out, you can climb the Belfry. The stairs go up the tower of the rebuilt Cloth Hall and finish under the old bells. From the top, on a clear day, the geography of the salient is in front of you as a flat green plate. You can see Saint Martin's Cathedral next door, also rebuilt. Saint George's Memorial Church, built in the 1920s by British public subscription. The market square below. The line of the city ramparts, designed in the 17th century by Vauban. The Menin Gate, where the names of the British missing up to 15 August 1917 are carved into the limestone, and where the Last Post has been played every evening at eight o'clock since 1928, with breaks only during the German occupation of 1940-44. East and north, the battlefields. The cemeteries are not visible from here but the visitor knows where they are by now.

The museum is built around the principle that no exhibit can substitute for the ground. It catalogues itself partly as a starting point. Maps in the shop direct visitors to Sanctuary Wood, Hill 62, Tyne Cot, Polygon Wood, Langemark, Essex Farm, the John McCrae Memorial Site where In Flanders Fields was written. The Lange Max Museum to the east covers the occupied German side; Museum Godshuis Belle in Ypres holds local artefacts. Everything is within an hour's drive. The Poppy Bracelet that you have been wearing all morning is taken back at the door. The four lives that you have followed through the exhibits do not end when you leave. They end somewhere out there, in a field, under one of the white stones. The museum's last suggestion is to go and find them.