Millions danced, cheered and set off fireworks in an all-night football induced delirium after Spain's first World Cup triumph.
The centre of Madrid became a sea of red and gold - the national colours - as huge crowds poured onto the streets to celebrate Spain's nailbiting 1-0 extra-time win over the Netherlands with a late goal from Andres Iniesta.
"Iniesta Presidente! Iniesta Presidente!" chanted one group of fans as they marched along the centre of the Gran Via, the Spanish capital's main thoroughfare in the early hours of Monday, amid baking heat.
Others imitated bullfighters and waved large Spanish flags over passing cars while chanting "Ole!"
A crowd estimated by Spanish media at more than 250,000 watched the match on giant screens in a fan park in a one-kilometre (half-mile) stretch of the street.
"We are very proud and very happy, I thought it would go to penalties, Iniesta saved us. We deserved it after winning the European championship in 2008," said 18-year-old Raul as passing cars honked their horns.
Some 75,000 people watched the match in the Catalan capital of Barcelona at an outdoor fan park and some 20,000 people stayed at the site to celebrate Spain's historic win, police said in a statement.
Police arrested 21 people for causing a disturbance by setting fire to garbage bins or breaking windows. Seventy-four people were injured, including 21 who required hospital care. Twelve police were among the injured.
In the northeastern Basque Country, which like Catalonia has a vocal separatist movement, three people were arrested for assaulting supporters of Spain's national team, police said.
Nearly 14 million people - out of a population of about about 45 million - watched Spain defeat Holland and win the World Cup on television, according to ratings firm Barlovento Comunicacion.
"All of Spain experienced last night how a lifelong dream became reality," top-selling daily newspaper El Pais wrote in an editorial.
Several groups were formed on Facebook calling on the government to declare Monday a national holiday to allow fans to recover from the festivities.
The squad headed back to Madrid and over one million fans are expected to line the streets of Madrid to watch as they parade through main streets on a open top bus from 7:00 pm (1700 GMT).
Prime Minister Jose Luis Rodriguez Zapatero will host a reception for the team at his official residence before the victory parade.
"This has been an epic match, I suffered like never before," Zapatero told Cadena Ser radio after the match.
"Champions," wrote right-wing newspaper ABC on its front page below a photo of Real Madrid keeper Iker Casillas holding up the World Cup trophy, surrounded by his teammates.
The World Cup win comes as Spain struggles to revive its economy and reduce its unemployment rate of around 20 percent, the second highest in the 27-nation European Union.
"The national squad is a metaphor for what Spain could be if we are willing to apply the same criteria which led to its success," wrote ABC in an editorial.
Sports daily AS said on its front page that Iniesta "scored the most important goal in our history" while the Marca sports daily Marca said his goal "lifted Spanish football to the highest possible level."
Four minutes from the final whistle, Iniesta collected a pass from Cesc Fabregas to fire home from close range and win the match.
Spain won the 2008 European Championships but had never even reached a World Cup final before.