The small, fabulous Igreja de São João, which faces the Templo Romano, was founded in 1485 by one Rodrigo Afonso de Melo, count of Olivença and the first governor of Portuguese Tangier, to serve as his family’s pantheon. It is still privately owned, by the Duques de Cadaval, and notably well kept.
Behind its elaborate Gothic portal is a nave lined with fantastic floor-to-ceiling azulejos produced in 1711 by one of Portugal’s best-known tile-makers, António de Oliveira Bernardes. The grates in the floor expose a surprising underworld: you can see a deep Moorish cistern that pre-dates the church and an ossuary full of monks’ bones. In the sacristy beyond are fragments of even earlier azulejos.
After exploring the church, head next door to the Palácio Cadaval with its collection of illuminated manuscripts, Arraiolos carpets and 18th-century paintings of Portuguese royals.