Winner: La Sagrada Familia
Where is it?
What is it?
Antoni Gaudi's famous unfinished basilica (work still continues on it more than 120 years after building began). Though the cranes and workmen distract from its beauty, La Sagrada Familia is an impressive feat of human vision and ambition.
Alternatively... There's nothing quite like Gaudi architecture, so if you want something similar, you'll have to see more Gaudi. Parc Guell is his most famous work after La Sagrada Familia.
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