The Frietmuseum is exactly what it sounds like — a museum dedicated to the history of Belgian fries, housed in a medieval merchant's house on Vlamingstraat. The collection traces the potato's origins in South America through its arrival in Europe and eventual transformation into the Belgian friet, which is different from French or British chips in several important ways: thicker, cut from specific potato varieties, fried twice, and eaten with mayonnaise rather than ketchup. The museum makes a reasonable case that the "French" fry is in fact a Belgian invention.
It is unabashedly quirky, and the exhibits include period cooking equipment, advertising posters, and a gallery of different potato varieties. Children find it entertaining; adults find it more diverting than they expect. There is a frituur (chip shop) in the basement that serves what may be the most philosophically consistent fries in the world.