While the Barcelona Cathedral may be the city’s more famous church, Santa Maria del Mar is just as impressive, and a masterpiece of Catalan Gothic style. The basilica was built in just 54 years—begun in 1329 and completed in 1383—and its interior is austere but architecturally dazzling. Slender 60-foot-high columns set far apart from one another give the impression of lightness and space, while the enormous, brilliantly colored stained-glass rose window at the church's western end allows sun to flood the space. Guided tours of the rooftop are conducted for 8 euros (about $9). The church also hosts regular classical concerts.