I just got back from a family vacation there. I was tired that day, it was hot and crowded, and I started thinking, "I wonder if this will be worth it."
I found myself astounded, struck speechless, and moved to tears. I was in awe.
Gaudi is someone we software engineers should revere. He made things precisely and powerfully functional while also making them beautiful.
Do not miss seeing Sagrada Familia if you ever get the chance.