4 Best Sights in Lisbon, Portugal

The large domed edifice is the former church of Santa Engrácia. It took 285 years to build, hence the Portuguese phrase "a job like Santa Engrácia." Today, the building is Portugal's National Pantheon, housing the tombs of the country's former presidents as well as cenotaphs dedicated to its most famous explorers and writers. A more recent arrival is fado diva Amália Rodrigues, whose tomb is invariably piled high with flowers from admirers.

The openwork balconies and domed turrets of the fanciful Belém Tower make it perhaps the country's purest Manueline structure. The UNESCO World Heritage site was built between 1514 and 1520 on what was an island in the middle of the Tagus River to defend the port entrance, and it's dedicated to Saint Vincent, the patron saint of Lisbon. Today the chalk-white tower stands near the north bank—evidence of the river's changing course. Cross the wooden gangway to check out the cannons, then climb the steep, narrow, winding staircase to the top of the tower for a bird's-eye view across the Tagus. Then, descend to the former dungeons.

Stretching for more than 18 km (11 miles), this aqueduct began providing Lisbon with clean drinking water in 1748. An imposing section of 35 arches—including one said to be the world's highest ogival (pointed) arch—stride across the Alcântara River Valley. Nearer the city center, another 14 arches run 200 feet along the Praça das Amoreiras, ending in the Mãe d'Agua reservoir ( Praça das Amoreiras 8), where you can explore equipment. Art lovers are in for a treat, too: Immersivus Gallery ( 91/065–8479,  portugalagenda.com) shows feature works by artists like Klimt, Kahlo, or Van Gogh projected onto walls and water, transforming them into a giant canvas.

Capping the post-earthquake restoration of Lisbon's downtown, the Arco Triunfal, as it's also known, was planned almost 50 years before the Parisian Arc de Triomphe. Its rooftop offers a splendid viewpoint from which to admire the handsome buildings around Praça do Comércio. Access to the terrace is via an elevator and then up two narrow winding flights of stairs. Once at the top, children delight in ringing a giant bell, while grown-ups can stand at the foot of the giant sculptures of Glory crowning Genius and Valour and revel in views of the Tagus River in one direction and the shopping, drinking, and dining strip of Rua Augusta in the other. The red-roofed houses and grand religious buildings that climb up the surrounding hillsides complete the dramatic scene. Back down in the square, you can identify other statues on the main facade by António Víctor de Figueiredo Bastos: from the left, a reclining figure representing the Tagus, followed by Viriato, native scourge of the Romans, and Vasco da Gama; and on the right, the Marquês de Pombal, medieval national hero Nuno Álvares Pereira, and the Douro River.