The Cathedral of Our Lady Immaculate (Cathédrale de Monaco, also known as Saint Nicholas Cathedral) is located in Monaco-Ville on Le Rocher, close to the Prince’s Palace. Built in the late 19th century from white limestone, it is the main Roman Catholic cathedral of Monaco and the burial place of members of the Grimaldi family, including Princess Grace. The cathedral is primarily an indoor religious site, with a serene interior featuring a high altar, modern religious artworks, and a grand organ, while the exterior square offers pleasant outdoor space for quiet reflection.

Entry to the cathedral is free of charge, as it is an active place of worship. It is open daily, usually from morning until early evening, though access may be limited during Mass, religious ceremonies, and special events, particularly on Sundays and major feast days. There are no tickets or fixed visiting schedules for tourists, but visitors are welcome outside service times to explore quietly. Organ concerts and special services may be held seasonally, especially around religious holidays.

Visitors should dress modestly and respectfully, with shoulders and knees covered, and maintain silence inside the cathedral. Photography is generally allowed when services are not in progress, but flash and disruptive behavior are discouraged. The cathedral can be visited year-round, with spring and summer offering the most comfortable weather for exploring Le Rocher. The site is easily accessible on foot, though the surrounding streets are steep, so comfortable walking shoes are recommended.