Museu Nacional d'Art de Catalunya

The Museu Nacional d'Art de Catalunya occupies the Palau Nacional, the domed palace built on Montjuïc for the 1929 International Exhibition, and it would be worth the walk up from Plaça d'Espanya for the building and the view alone. Its cascading steps, the fountains and the Magic Fountain below it form one of the great urban vistas in the city. Inside, the museum tells the story of art in Catalonia from roughly the tenth century to the middle of the twentieth, and its first section is the reason art lovers travel here. In the early twentieth century, as collectors began stripping frescoes from the small Romanesque churches of the Pyrenees and selling them abroad, Catalan experts removed many of the finest murals from their walls and brought them to Barcelona to protect them. Today they are displayed in reconstructed apses and chapels that recreate the shape of the original churches, so you walk into a curved space and find yourself beneath an enormous painted Christ in Majesty, as worshippers in a mountain village did nine hundred years ago. The apse from Sant Climent de Taüll, with its staring, hieratic Christ, is the masterpiece, and few museums anywhere offer anything comparable. The Gothic galleries follow, with altarpieces glowing with gold, and the modern collection is a revelation for anyone who knows little about Catalan art, with modernista furniture and interiors by Gaudí and his contemporaries, paintings by Ramon Casas and Santiago Rusiñol, and work by Picasso and other twentieth-century artists. A smaller collection of Renaissance and Baroque art includes works by major European painters. The huge oval hall beneath the dome, built for ceremonies and concerts, is one of the most impressive interiors in the city.

Do not leave without going up to the roof. Terraces on top of the Palau Nacional have viewpoints with a sweeping panorama over Barcelona, from Plaça d'Espanya and the Eixample to the Sagrada Família, Tibidabo and the sea, and they are included with museum admission; a small separate fee covers the terraces alone. Combine a late-afternoon museum visit with sunset from the roof, then walk down the steps to the Magic Fountain if a show is scheduled.

Saving money: the MNAC is one of Barcelona's best-value museums. Admission is free on Saturday afternoons and on the first Sunday of each month, as well as on a few special days of the year, and visitors under sixteen or over sixty-five enter free at all times. Free slots still require booking online, and they are popular, so reserve as soon as you can. A standard ticket is valid for two days within a month, so you can split this big museum into two shorter visits, which is a good idea: seeing everything in one go is exhausting. The museum is closed on Mondays, and Sunday hours are shorter, ending in the early afternoon.

Visiting well: if time is short, focus on the Romanesque galleries and the roof, which will take about ninety minutes; allow three hours or more to see the Gothic and modern collections properly. The walk up from Plaça d'Espanya is long and uphill, but escalators run alongside the steps for much of the way. The museum has a café and a restaurant with views, and the gardens of Montjuïc, the Fundació Joan Miró and the castle are all within reach, so this can anchor a full day on the hill. For families, the Romanesque apses, with their monsters, saints and bright colours, are surprisingly engaging for children, and free entry for under-sixteens makes it an easy choice.