San Maurizio al Monastero Maggiore

San Maurizio is the place Milanese people take visitors when they want to see jaws drop. From the street it looks like any sober Renaissance church; inside, the walls and vaults are covered from floor to ceiling in sixteenth-century frescoes, so densely painted and so well preserved that the church is regularly called the Sistine Chapel of Milan. It was built from the early 1500s as the church of the Monastero Maggiore, the most important Benedictine convent in the city, whose origins go back to the early Middle Ages. The building is divided in two by a frescoed wall. The front half was the public church, where the people of Milan heard mass; the back half was the nuns' choir, where the enclosed sisters followed the service unseen through a small grille. Today you can walk through to both, which is part of the fascination. The chief painter was Bernardino Luini, one of Leonardo's most gifted followers in Milan, and his work here, especially the scenes in the chapels and the portraits of the Bentivoglio family who sponsored the decoration, is among the finest Renaissance painting in the city. His sons and other Lombard painters continued the cycles in the nuns' choir, where an extraordinary Noah's Ark scene, with animals including unicorns lining up to board, delights children and adults. At the back of the nuns' hall stands a sixteenth-century organ by the Antegnati family, still used for concerts. Next door, the former convent houses Milan's Civic Archaeological Museum, which incorporates a Roman tower and a stretch of the city's ancient walls. San Maurizio is free to enter, quick to visit and among the most rewarding stops in Milan.

Visiting: the church is generally open from Tuesday to Sunday, from morning to late afternoon, and closed on Mondays; entry is free. Groups need to book, and access can be limited at busy times or during concerts and events, so individual visitors should arrive early on weekends. Photography without flash is usually allowed. The adjoining Civic Archaeological Museum has its own ticket and timetable.

How to see it: spend a few minutes in the public church looking at the chapels along both sides and the great dividing wall, then walk through to the nuns' choir and look up at the vaults and the upper loggia. Find the Noah's Ark scene, the portraits of the Bentivoglio donors and the organ. Concerts of early and sacred music are held here from time to time, and hearing the organ in this setting is memorable if your dates line up.

Combining it: San Maurizio is on Corso Magenta, a short walk from the Cairoli and Cadorna metro stops and from the Sforza Castle. Santa Maria delle Grazie and the Last Supper are further along the same street, and Sant'Ambrogio is ten minutes south, so these three churches make a natural half-day loop.