Valencia, Spain - Pope Benedict XVI praised marriage between a man and a woman as part of God's "loving plan," defending the traditional family Sunday at a Mass in Spain attended by hundreds of thousands.
The service in a Valencia park was the highlight of his two-day trip to this mainly Roman Catholic country, whose Socialist government has angered the Vatican by introducing liberal reforms such as gay marriage and fast-track divorce.
The pope, wearing green vestments and a gold miter, stressed that the family is "founded on indissoluble marriage between a man and a woman."
Every family has its origin in God, he said, and "at the origin of every human being there is not something haphazard or chance, but a loving plan of God."
He spoke from an altar erected on a bridge over a dry bed that was once the city's river.
Many of the pilgrims wore hats, T-shirts and backpacks with the Vatican's yellow and white colors and had camped overnight in parkland nearby. Throughout the service they fanned themselves for relief from the summer heat.
There were wide discrepancies in crowd counts.
The Vatican said local organizers estimated some 1.5 million people attended the Mass and another 700,000 watched by means of giant screens set up around the city.
But local police said about 1 million people were at the park, while witnesses and news reports estimated the crowd at less than half that size.
Prime Minister Jose Luis Rodriguez Zapatero had a 15-minute meeting with Benedict on Saturday afternoon but he did not attend Sunday's Mass. That was left to King Juan Carlos and Queen Sofia and two government ministers, who also escorted him afterward to the airport.
The pope left for Rome on an Iberia airliner shortly after 1 p.m., ending a trip that lasted just 26 hours.
Benedict came to Spain to address a worldwide church meeting on the family and support traditional values in Spain.
In a series of addresses after arriving from Rome, he called the family "a unique institution in God's plan" and stressed the church considers a marriage proper only if between a man and a woman.
"I wish to set forth the central role, for the church and for society, proper to the family based on marriage," the German-born pope said.
Spain recently legalized gay marriage. Zapatero's government also has made it easier for Spaniards to divorce and halted a plan by a previous, conservative government to make religion classes mandatory in public schools.
Many Spaniards have drifted away from the church in the three decades since the fall of the Gen. Francisco Franco dictatorship, under which it enjoyed special privileges.
Spain has passed from being a bastion of Roman Catholicism to a predominantly lay society in less than a generation. Statistics show that while 80 percent of Spaniards still call themselves Catholics, only 42 percent believe in God and 20 percent go to Mass.