: Massive crowds, strict dress code (shoulders and knees covered), and narrow, steep stairs for the dome climb. Basílica de la Sagrada Família ClosedBarcelona, Spain
Basilica of the National Shrine of the Immaculate Conception ClosedWashington, DC basilica
Gaudí's unfinished masterpiece is praised for its unique "tree-trunk" columns and forest-like interior. Saint Mark's Basilica ClosedVenice, Metropolitan City of Venice, Italy : Massive crowds, strict dress code (shoulders and