Barcelona’s Basilica de la Sagrada Família is famous for being unfinished. Designed by famed architect Antoni Gaudí, the impressive neo-Gothic church draws over 4.5 million visitors a year. But since construction began in 1882, the basilica is yet to be fully completed.

However, what many visitors (and even authorities) didn't realize was that since its inception, the construction of the Sagrada Família was never fully legal. In 1885, when Gaudí applied for a building permit, he received no response from the city of Barcelona.

After his death in 1926, multiple architects continued construction on the Roman Catholic church to execute Gaudí's full vision for the structure.

It was only in 2016 that authorities discovered that neither Gaudí, nor the architects carrying out his plans, had ever received an official building permit from the city.

Finally, after 137 years of unlicensed construction, a building permit has been granted. The seven-year license specifies that the structure can reach a maximum of 172 meters high and will cost approximately 374 million euros.

The new license outlines the target completion date as 2026, which will mark the centenary of Gaudí's death.