The Mafra National Palace and Convent, 8 km (5 miles) southeast of Ericeira, has been classified as UNESCO World Heritage since 2019. From the 17th through 19th centuries this was a favorite residence for the Portuguese court. In 1711, after nearly three years of a childless union with the Hapsburg queen, Maria Anna, a despairing King João V vowed that should the queen bear him an heir, he would build a monastery dedicated to St. Anthony. In December of that same year, a girl—later to become queen of Spain—was born; João's eventual heir, José I, was born three years later. True to his word, King João V built an enormous monastery, which still looms above the small farming community of Mafra. The original project—entrusted to the Italian-trained German architect Johann Friedrich Ludwig, invariably known in Portugal as João Frederico Ludovice—was to be a modest facility that could house 13 friars. Construction began in 1717 and continued until 1755, with the final result being a rectangular complex containing a monastery large enough for hundreds of monks as well as an imposing basilica and a grandiose palace that has been compared to El Escorial outside Madrid, Spain. The numbers involved in the construction are mind-boggling: at times 50,000 workers toiled. There are 4,500 doors and windows, 300 cells, 880 halls and rooms, and 154 stairways. Perimeter walls that total some 19 km (12 miles) surround the park.
The highlight of any visit to the monument is the magnificent baroque library: the barrel-vaulted, two-tiered hall holds almost 40,000 volumes of mostly 16th- through 18th-century works and a number of ancient maps. Protection from insects is provided by bats, which slip into the room at night through tiny holes that were bored through stone under the windows for the purpose. The basilica, which was patterned after St. Peter's in the Vatican, contains 11 chapels and six organs, which are played simultaneously for splendid concerts at 4 pm on the first Sunday of every month except January and February. At the time of writing the basilica is closed for renovation, so there are no organ concerts. However, the carillons—the world's largest ensemble, with 45 bells in the north tower, 53 in the south—are still played every Sunday, at 4 pm in winter and 5 pm in summer. When you're in the gilded throne room, notice the life-size renditions of the seven virtues, as well as the impressive figure of Hercules, by Domingos Sequeira. Guided visits may be booked in advance at an additional cost.