'La Sagrada Familia' in Barcelona, whose construction began in 1882, will be completed in 2026 after 144 years of construction.

In a statement made by the Guinness Book of Records, it was stated that La Sagrada Familia, the world's longest ongoing active construction project, will be completed in 2026. La Sagrada Familia Basilica is one of the most famous architectural monuments inherited by Catalan architect Antoni Gaudi in 1883.

Gaudi, who died in 1926 after being hit by a tram, was unable to complete La Sagrada Familia. Historical processes such as the Spanish Civil War and World War II were also effective in the failure to complete the building. Although the building is planned to be completed by 2026, work on the sculptures and decorative details and the controversial staircase leading to the main entrance is expected to continue until 2034.