Church leaders have agreed to pay millions of pounds to authorities after it emerged the work was actually illegal as it is still marked on the property register as an empty plot.
Despite work beginning in the 19 century, Spanish architect Antoni Gaudi's iconic landmark has been unfinished all that time.
While not due for completion until 2026, the church receives 4.5 million visitors every year.
Writing on Twitter, Barcelona Mayor Ada Colau said the agreement was great for all parties.
"The Sagrada Familia is an icon and the most visited monument in our city.
"After two years of dialog we have made an agreement that will guarantee the payment of the license, secure access to the monument and facilitate local life with improvements to public transport and redevelopment of the nearby streets."
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