Barcelona's towering Sagrada Familia basilica will reach its maximum height on Friday, though the magnum opus of Catalan architect Antoni Gaudi remains years away from completion.

A crane was placing the upper arm of a cross atop the "Tower of Jesus Christ," the church's soaring central piece, which will stand 172.5 meters (566 feet) above the city, the church said.

While the unfinished monument is already the world's tallest church, with Friday's addition the Sagrada Familia — still surrounded by building cranes and scaffolding — will inch closer to being done.

The first stone of the Sagrada Familia was placed in 1882, but Gaudi never expected it to be completed in his lifetime. Only one of its multiple towers was finished when he died at the age of 73 in 1926 after being hit by a tram.

In recent decades, work has sped up as the basilica became a major international tourist attraction with people around the world visiting Barcelona to see the monument, enthralled by Gaudi ’s radical aesthetic that combines Catholic symbolism and organic forms.

The inside of the "Tower of Jesus Christ" is still being worked on. But topping the central tower, which soars above the transept, has been a priority ahead of celebrations this June that will mark the centenary of Gaudi’s death.

The scaffolding surrounding the central tower is expected to be removed by June, in time for the inauguration of the "Tower of Jesus Christ."

As Gaudi had planned, the cross has four arms so its shape can be recognized from any direction, said Sagrada Familia's rector, Rev. Josep Turull. If Barcelona’s city government will allow it, the original plan also includes a light beam shining from each of the cross’s arms, symbolizing the church’s role as a spiritual lighthouse, he added.

Millions of tourists visit the Sagrada Familia every year, and entrance fees largely fund the ongoing construction.

This year, the Sagrada Familia will hold several events to celebrate the Catalan Modernist's legacy, which includes other stunning buildings in Barcelona and elsewhere in Spain.

The Sagrada Familia became the world's largest church last October, when it rose above the spire of Germany’s Ulmer M nster, a Gothic Lutheran church built over 347 years starting in 1543. That church tops out at 161.53 meters (530 feet).

At the base of the cross to be installed Friday afternoon at Sagrada Familia, a prayer verse is inscribed from the Gloria that Catholics recite at Mass, said Turull, the church's rector.

It reads: "You alone are the Holy One, you alone are the Lord, you alone are the Most High."