Tourists and pedestrians walk past the Sagrada Familia, the largest unfinished Catholic church in the world and part of a UNESCO World Heritage Site

tourists visit sagrada familia travelers visit famous religious site sagrada familia church architect antoni gaudi sagrada familia under construction roman catholic church roman catholic catholic religion iglesia spain incredible history heritage culture decoration altar renowned architecture antoni gaudi antoni gaudi work barcelona unesco world heritage site unesco world heritage unesco church under construction construction site crane working iconic church sagrada familia towers catholicism famous place christianity travel destination spain architecture spanish religious architecture catalonia building exterior crane machinery religion site religious building unfinished heritage building series famous religious building tourism massive tourism sightseeing