La Tour Jean-sans-Peur is one of the rare medieval fragments left in central Paris outside the Marais. The tower once belonged to the Hôtel de Bourgogne, the fortified residence of John the Fearless, Duke of Burgundy.
Its narrow stair and stone rooms make a compact visit, but the survival alone is striking in a neighbourhood now better known for shopping streets and covered passages. It is a good stop if you want to see a rougher medieval layer of Paris.