During the mass, the basilica's creator, architect Antoni Gaudí, was also honored on the 100th anniversary of his death.
The church is still not completely finished, but the centrally located Tower of Jesus Christ (La torre de Jesucrist), now complete and over 170 metres high, marks the end of an important phase of the construction project.
The inauguration culminated with a light show that illuminated the Christ the Redeemer Tower and the sky over Barcelona in a visual tribute to Gaudí's creativity and vision.
Antoni Gaudí died on June 10, 1926, at the Santa Creu Hospital in Barcelona's old Raval district after being struck by a tram.
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