Spain's "indignant" activists began their last and longest protest march on Saturday, leaving from the northeastern city of Barcelona to cover 650 kilometres on their way to a major Madrid rally on July 24.
Two other marches set off earlier this week, from Valencia in the east on Monday and Cadiz in the south on Thursday, spreading the message of their anger at unemployment, welfare cuts and corruption.
Some 50 marchers left Barcelona early in the morning to applause from passers-by and sympathisers, expecting to pick up more en route.
They carried sleeping bags, groundsheets and prophylactics against insect bites, sunburn and muscle cramps. The party also included a doctor and a nurse.
Some walking and others cycling, they planned to pass through 29 towns and villages, holding a meeting at each stop on the 652-kilometre (407-mile) route.
"It's a further step for the indignant," said Rafael de la Rubia, international coordinator of the movement World without War, who is well used to marching for a cause.
"First we took to the streets, then the squares, and now the highways," he added.
"After that, we will take Europe."
The protest movement started in Madrid on May 15 and fanned out nationwide as word spread by Twitter and Facebook, bringing tens of thousands of people into city squares around Spain ahead of May 22 local elections.
On Sunday, about 200,000 protesters packed the streets of Madrid, Barcelona and other major cities to vent their anger, according to estimates by the Spanish media and some regional authorities.
On Wednesday some 200 rallied near the Spanish parliament after camping out overnight to protest plans to overhaul workers' collective bargaining rights.
The "indignants" have inspired similar offshoot movements in other European countries, notably Greece, where the government is also trying to implement a strict austerity programme to avoid defaulting on its loans.
The Spanish central bank said last week the recovery in Spain's beleaguered economy would likely remain slow, and that unemployment could remain high for the foreseeable future.
Spain announced Friday it will reduce a government spending cap by 3.8 percent in 2012 as it fights to retain the trust of markets.