At the very top of 512m-tall Tibidabo hill, overlooking the Parc d'Atraccions, this landmark basilica is meant to be Barcelona’s answer to Paris’ Sacré-Cœur. Built from 1902 to 1961 with some Modernista influence, it's certainly as visible as its Parisian counterpart, and even more vilified by aesthetes. It’s actually two churches, one above the other. The top one is surmounted by a giant Christ statue and has a lift up to the roof for panoramic (and often wind-chilled) views.
From March to December, bus T2A runs here directly from Plaça de Catalunya. Alternatively, take train line L7 to Avinguda Tibidabo, then the 'Funibús' shuttle up the hill (check schedules online).