Lisbon Cathedral

The Sé, as Lisboetas call their cathedral, is the oldest church in the city and looks it: a stern block of stone with two battlemented towers flanking a rose window, more fortress than temple, built that way because it was begun in the years after 1147, when Afonso Henriques took Lisbon from the Moors and needed a church that could double as a stronghold. It stands on the site of the city's main mosque, on the slope between the Baixa and the castle, and tram 28 squeals past its door, which makes it the most photographed street corner in Lisbon. Over the centuries the cathedral has been altered by earthquakes and fashions — a Gothic ambulatory and royal tombs were added in the fourteenth century, the 1755 earthquake brought down parts of the building and its contents, and a twentieth-century restoration stripped away later additions to bring back the Romanesque look. Inside, the nave is dim and austere, and the main body of the church is open for worship and quiet visits. The paid areas are where the depth lies. The Gothic cloister has been the focus of long-running archaeological excavations that have uncovered remains of a Roman street, Islamic-era structures and medieval buildings beneath the cathedral, an unusually vivid cross-section of two thousand years of the city. The treasury, up a staircase, displays gold and silver liturgical objects, vestments and relics. Tickets are inexpensive, and visits are not available on Sundays, when the cathedral is given over to services.

The cathedral is tied to Lisbon's favourite saint. Saint Anthony, known everywhere else as Anthony of Padua, was born in Lisbon in the late twelfth century in a house that stood just across the square, where the church of Santo António now stands, and he was baptised in the Sé's font. His feast in June is the city's biggest party, when the old neighbourhoods fill with grilled sardines, paper garlands and music, and the cathedral sees mass weddings of couples who marry on his day. Lisbon's bishop, and later patriarch, has his seat here, and the building has been the stage for royal ceremonies since the Middle Ages.

Inside, take a slow loop. The nave and its Romanesque arches set the mood; look for the Gothic tombs in the chapels of the ambulatory, including a knight with his dog at his feet, and the elaborate eighteenth-century nativity scene by Machado de Castro. Then head to the cloister, where walkways run over and around the excavations, with information panels to help make sense of the layers. Up in the treasury, the highlights are the gilded monstrances and the reliquaries associated with Saint Vincent, the patron of Lisbon, whose relics according to legend were brought to the city on a boat guarded by ravens — the birds that now appear on the city's coat of arms.

The Sé takes forty-five minutes to an hour and fits naturally into a walk between the Baixa and the castle. Visit when it opens, then climb to the Miradouro de Santa Luzia and the castle, or go the other way down to the Baixa and Praça do Comércio. The classic photograph — a yellow tram passing in front of the cathedral towers — is best taken from the slope just uphill. Dress respectfully, keep voices low during services, and remember there are no tourist visits on Sundays.