Just a short walk from the center of the neighborhood lies a building that perfectly embodies Bairro Alto’s talent for surprises: the Church of Saint Roch, or Igreja de São Roque. From the outside, its plain, Mannerist facade is so simple you might walk right past it. But step inside and you will find one of the most opulent interiors in the Catholic world. This was the first Jesuit church in the Portuguese world, designed specifically with a wide, column-free nave to make preaching easier for the crowds. The crown jewel here is the Chapel of Saint John the Baptist. In the 1740s, King John the Fifth commissioned this chapel to be built in Rome using the world’s most precious materials, including lapis lazuli, agate, and rare marbles. It was even blessed by the Pope before being disassembled, shipped in parts, and reconstructed right here in Lisbon. It is widely considered one of the most expensive chapels ever built in Europe, a glittering display of the global wealth of the Portuguese Empire.