Pope Leo XIV is midway through a landmark visit to Spain that has drawn enormous crowds and generated significant international attention, combining moments of cultural pageantry with substantive papal statements on artificial intelligence, mental health, and domestic violence. The visit has already included an open-air mass in Madrid attended by an estimated 1.5 million people and an unprecedented address to the Spanish parliament — a first for any pontiff — before the pope moved on to Barcelona, the capital of the Catalonia region in northeastern Spain.

In Barcelona, the pope was greeted with a striking display of local tradition: more than 100 members of the Castellers de Vilafranca, a group dedicated to the Catalan practice of building human towers, constructed a 10-metre-high structure before a crowd of around 40,000 people. The human tower, known as a castell, is widely regarded as a symbol of collective effort and Catalan cultural identity. Pope Leo also won visible approval by mixing Spanish and Catalan during his speeches, drawing applause each time he switched languages. On Wednesday, he is scheduled to bless the new central tower of the Sagrada Família — the iconic Antoni Gaudí-designed basilica — now the world's tallest church, and celebrate mass there.

At a prayer vigil on Tuesday evening, the pope heard personal testimonies from young people and addressed several pressing social issues. After a young woman recounted her attempt to take her own life, Leo called on public health systems to prioritise what he described as the "invisible and widespread malaise" of mental health, saying that "there is something deeply wrong with a certain notion of progress that subjects people to pressures, expectations and tensions that compromise healthy balances." A second testimony, from a woman whose father had attempted to kill her mother, prompted the pope to condemn "a toxic climate in family relationships marked by abuse and oppression and, in particular, by violence against women."

The visit comes weeks after Pope Leo published his first major encyclical, titled Magnifica Humanitas, focused on artificial intelligence. In that document — released on 25 May — the pope warned that reduced human oversight of AI-powered weapons systems increases the risk of prolonged conflict, and called for AI to be, in his words, "disarmed." He emphasised the right to work and personal dignity in the face of rapid job displacement driven by AI adoption across major technology companies. Christopher Olah, co-founder of AI research company Anthropic, was present at the encyclical's launch and acknowledged that "the questions raised by AI are bigger than the AI research community."

The papal tour continues later this week with a visit to the Canary Islands, the Spanish Atlantic archipelago located off the northwestern coast of Africa, where Pope Leo is expected to meet migrants making the dangerous crossing from West Africa and pay tribute to those who have died attempting the journey. The visit as a whole has prompted reflection on the state of Catholicism in Spain, where religious observance has declined steadily for decades, yet the scale of the crowds suggests enduring or renewed interest, particularly among younger Catholics.