Chartres’s stunning Cathedrale Notre-Dame is one of the most beautiful surviving creations of the Middle Ages. Arguably the finest example of early Gothic architecture in Europe, the cathedral retains several of its original 12th-century stained-glass windows; the rest of the windows and the magnificent sculptures on the main portals date from the 13th century, as does the carved floor in the rear of the nave. You can enter the 9th-century crypt only from La Crypte, opposite the cathedral’s south entrance. (02 37 21 75 02; www.cathedrale-char-tres.com. Open Easter through Oct. daily 8am-8pm, Nov. through Easter daily 8:30am-7pm. No casual visits during mass. North Tower open May-Aug. M-Sa 9:30am-noon and 2-5:30pm, Su 2-5:30pm; Sept.-Apr. M-Sa 9:30am-noon and 2-4:30pm, Su 2-4:30pm. Tower admission ‚4, ages 18-25 ‚2.50. Under-18 and some Su free.) Trains ran from Paris’s Gare Montparnasse (lhr. every hr. ‚23). From the station, walk straight, turn left into the pi. de Chatelet, turn right on r. Ste-Meme, then turn left on r. Jean Moulin.