The Waag is the ornate weighing house that dominates the Waagplein, with a stepped Renaissance gable, a carillon, and a clock tower whose mechanical jousting knights ride out on the hour. The building was originally a chapel in the 14th century, converted to a public weigh-house in 1582 after the church changed hands during the Reformation. The cheese-weighing function remained until well into the 20th century.
Upstairs the Hollands Kaasmuseum (Dutch Cheese Museum) tells the story of cheese-making and trade in the Netherlands — old presses, milking equipment, photographs of the market through the centuries, and tasting opportunities. It is small, an hour at most, and works well as a follow-up to the Friday-morning market. The tourist information office occupies the ground floor.