There are several historical sites in Lisbon that merit special mention for their cultural or architectural significance. One such landmark is Palácio Fronteira, sited near the city’s Benfica area. The mansion is noted for its stunning 17th-century tiled panels. On the other side of the city is the Panteão Nacional-Church of Santa Engrácia where the tombs and cenotaphs of many eminent Portuguese citizens are situated. Under the streets in the Baixa (downtown) district, the foundations of a 13th-century wall, the D. Dinis Wall, can be viewed as part of a permanent exhibition. Meanwhile, those interested in religious sites have two very special churches to investigate, Igreja de São Domingos, known for its fire damaged interior, and Igreja do Carmo, one of the few buildings to have withstood the great 1755 earthquake. Meanwhile, another subterranean historical site is the Núcleo Arqueológico, sited under a bank. And once a year an opportunity arises to go underground and explore the fascinating nearby Galerias Romanas. It’s worth waiting in the long queues for! Over towards Alfama, the Sé de Lisboa Cloisters surround the foundations of a Moorish mosque. In fact, the excavations are linked to the Museu do Teatro Romano, sited further up the hill where the ruins of a Roman theatre can be viewed. Away from the city centre is Museu da Água Príncipe Real-Reservatório da Patriarcal, a 19th-century reservoir and cistern complex, again hidden underground and another one of Lisbon’s more unusual historical sites.