Monaco Cathedral

The Cathedral of Our Lady Immaculate stands near the seaward edge of the Rock, a few minutes' walk from the Palace Square, and it is the spiritual heart of the principality. It was built between 1875 and 1911 on the site of an older church dedicated to Saint Nicholas, in a Romanesque-Byzantine style and in white stone quarried at La Turbie, which gives the facade a pale, almost luminous look against the blue of the sky. The interior is cool and calm, with a high altar in white Carrara marble, an episcopal throne and, among the treasures, a late fifteenth-century altarpiece by the Nice painter Louis Bréa, one of the finest works of the Niçois primitive school. Most visitors come for the royal connections: this is the church where Prince Rainier III and Grace Kelly were married in 1956, and it holds the tombs of the princes of Monaco, including those of Rainier III and Princess Grace, which are marked by simple slabs and are often covered in fresh flowers. It is a working cathedral rather than a museum, so the atmosphere is quiet and respectful, and the visit is short but memorable.

Entry is free every day outside religious services, which makes it one of the best-value stops in Monaco. Smart dress is expected: shoulders must be covered, and short skirts and short shorts are not allowed, although Bermuda-length shorts are accepted. If you are visiting in summer, carry a light scarf or shirt in your bag so you can cover up on the way in.

Photography is usually tolerated in the nave when no service is under way, but keep your voice low, do not use a flash and step aside for anyone who has come to pray.

On Sunday mornings the 10 o'clock Mass is sung by the Cathedral Choir and Les Petits Chanteurs de Monaco, the boys' choir, from September to June, and it is a beautiful way to hear the building at its best, though it is a service and not a performance, so sit quietly and do not wander.

The organ deserves a mention. It sits in the great gallery above the entrance and has four keyboards, 79 stops and nearly 7,000 pipes after a complete rebuild completed in 2011, and organ concerts are sometimes held, which are worth looking out for if you are staying overnight. Two great days in the church calendar draw crowds: the feast of Sainte Dévote on 27 January and Monaco's National Day on 19 November both bring pontifical services, and the cathedral may be closed to casual visitors at those times.

The best way to fit the cathedral into a day is as part of a loop on the Rock. Start at the Palace Square for the Changing of the Guard at 11:55, walk down the lane to the cathedral, spend twenty minutes inside, then step out into the Saint-Martin gardens for the sea view and finish at the Oceanographic Museum or lunch in the old town. Allow half an hour if you are in a hurry, or an hour if you want to read the plaques and look at the altarpiece properly.

The nearby lanes are cobbled and slope gently, so wear comfortable shoes. If you need step-free routes, check access with the tourism office before you go. It is one of the few places in Monaco where history and everyday life sit side by side, and it is a gentler, quieter counterweight to the casinos and yachts below.