All year long (in French or in English)
Audio guided-tour: Feel free to explore all the secrets of the old town, its picturesque streets, old bridges and "tertres" (ramps and staircases) in a commented one-hour and a half visit using an audiophone.
Rental from the Chartres Convention and Visitors Bureau (1 audioguide: €5,5 - Price for the 2nd: €3)
Night walking tour "Lights of Chartres": A commented walk in the evening, to discover "Lights of Chartres": 27 monuments and sites in shimmering colours.