The city’s crowning glory is an outstanding example of Gothic architecture, representing a transition from the Romanesque. Construction began in 1176. The pyramidal tower in rose-colored stone was completed in 1439; at 141m (462 ft.), it’s the tallest one from medieval times. This cathedral is still in use; religious ceremonies, particularly on feast days, meld perfectly with the architectural majesty. Individual tourists can visit the tower only in the summer (you may have to wait to climb it). The Office de Tourisme organizes tours for groups; call for the schedule.

Four large counterforts divide the main facade into three vertical parts and two horizontal galleries. Note the rose window, which looks like stone lace. The facade is rich in decoration: On the portal of the south transept, the Coronation and Death of the Virgin in one of the two tympanums is the finest such medieval work. In the north transept, see also the facade of the Chapelle St-Laurence, a stunning achievement of the late Gothic German style.

A Romanesque crypt lies under the chancel, which is covered with square stonework. The stained-glass window is the work of Max Ingrand. The nave is majestic, with windows depicting emperors and kings on the north Strasbourg aisle. Five chapels cluster around the transept, including one built in 1500 in the Flamboyant Gothic style. In the south transept stands the Angel Pillar, illustrating the Last Judgment, with angels lowering their trumpets.

The astronomical clock was built between 1547 and 1574. It stopped during the Revolution, and from 1838 to 1842, the mechanism was replaced. Each day at 12:30pm, crowds gather to see its show of allegorical figures. On Sunday, Apollo drives his sun horses; on Thursday, you see Jupiter and his eagle. The body of the clock has a planetarium based on the theories of Copernicus. Close-up views of the clock are available Monday to Saturday from noon to 12:30pm; tickets (3€ adults, 2€ ages 5–18 and students) are on sale in the mornings at the post-card stand or from 11:45am at a kiosk in the south portal.