Pope Leo XIV has honoured Spain’s centuries-old tradition of religious devotion as a “school of faith” as he held Mass for a million people, and highlighted one of the most iconic expressions of Spanish popular piety with a procession over carpets of flower petals.

The head of the Catholic Church arrived in Spain on Saturday and urged its people to put an end to polarisation and work for unity.

For Sunday’s Mass and procession in Madrid, local organisers said 1.2 million people packed the Plaza de Cibeles and surrounding streets, with more trying to get in.

The crowd several rows deep cheered as the pontiff in his popemobile looped around the city centre plaza, with everyone eager to witness the first papal visit in 15 years.

The open-air Mass was held on the Catholic Corpus Domini feast day, which often features processions of faithful through towns and cities led by a priest carrying the Eucharist. In Spain, as in other predominantly Catholic countries, the processions often feature elaborate floral carpets arranged along the route.

According to Spanish organisers, the 16 flower carpets decorating the half-kilometre (half-mile) procession route off Plaza de Cibeles were prepared by a Spanish florists’ association from Galicia. Florists used more than 30,000 flowers, most in the yellow and white colours of the Holy See flag, for the decorative floral carpets.

At the end of the Mass, Leo carried a gilded monstrance, or container, holding a Eucharistic host and walked over the floral carpets, as children dropped additional petals before him and the crowd tossed petals from behind the barricades.