Pope Leo advocates for prisoner rights as he visits one of Spain's largest jails

Pope Leo, who has forcefully advocated for the rights of prisoners, visited one of Spain's largest prisons on Wednesday, urging the inmates to make amends for their crimes and commit to living better lives.

Speaking to detainees at a penitentiary outside Barcelona, in the first visit of a pope to a Spanish prison, Leo said a person's past "does not condemn the future but rather offers the possibility of changing our decisions and choices".

Leo, the first U.S. pope, is on a week-long tour of Spain in which he has warned that escalating conflicts have pushed the world into a profound crisis and urged better treatment of migrants.

The centrepiece of the pope's visit to Barcelona, the second of three stops on the tour, will come later Wednesday, when he will inaugurate the newest tower of the Sagrada Familia, the modernist basilica designed by Antoni Gaudi that has become the world's tallest church.

The Brians 1 penitentiary, built in 1991 about 40 km (25 miles) outside Barcelona, currently houses around 1,000 inmates.

"It’s a once-in-a-lifetime opportunity. I haven’t been able to sleep a wink," said Montse Benavente, an inmate who delivered a testimony before the pope about how she had struggled with her faith and the damage she had done to her family with her actions.

Leo last visited a prison in April, when he braved a heavy rainstorm in Equatorial Guinea during a four-nation Africa tour and heard the inmates cry out for freedom.

The late Pope Francis also advocated for prisoners' rights and visited a facility in Rome just four days before his death as he was recovering from double pneumonia.

One of the prisoners at the Barcelona facility told El Mundo they were very grateful for Leo's visit. "No one remembers us," said the person, identified as Mayte. "It is very easy to forget someone who is in prison."

-Reporting by Joshua McElwee; Additional reporting by Joan Faus; Editing by Charlie Devereux and Alison Williams/Reuters