La Cité du Vitrail Troyes

Housed in the barn of the 18th-century Hôtel-Dieu-le-Comte, this free museum dazzles with 25 works of stained glass reaching from the 12th to the 21st century – all visible at eye level. A highlight (quite literally) is the 16th-century Tree by Jessé of Laines-aux-Bois. There are regular workshops for children; see the website for details.