Velorama is the Netherlands' national bicycle museum, housed in a historic building in the Waalkwartier district. The collection covers nearly two centuries of bicycle history with over 250 machines, from early wooden draisines through penny-farthings and safety bicycles to racing machines and experimental designs. It's a more interesting museum than it sounds: the evolution of the bicycle is essentially the story of how ordinary people gained personal mobility for the first time, and the Dutch relationship with cycling gives it an extra dimension.
The museum is small enough to do properly in an hour and a half. Kids tend to enjoy it more than expected — some of the Victorian machines are genuinely strange to look at, and the design evolution is easy to follow without needing to read all the labels. It sits near the Waalkade, so it combines naturally with a walk along the river and a visit to Valkhof Park.