Barcelona, one of Europe's biggest tourist destinations, is starting to resemble a war zone.
Thousands of national police have been moved into the city to stop regional authorities holding an independence referendum on Sunday.
On Thursday, students and other activists began staging protests and sit-ins to defend what they see as their right to vote. The city is bracing for what could be the worst civil confrontation since democracy was restored in the 1980s.
"Neither side is listening to the other side anymore," Carles Castellanos, a 75-year-old retired teacher and prominent political activist, said.
"If the Spanish government had properly addressed the requests of Catalonia in the past and not rejected negotiations, it wouldn't have come this far. Now both sides have become more extreme in their positions."
Like many older Catalans, Mr Castellanos never imagined he would live to see his beloved city of Barcelona voting for independence.
He was imprisoned four times under the dictatorship of General Francisco Franco, a ruthless Spanish nationalist who suppressed Catalan language and culture from the 1930s until his death in 1975.
Now Castellanos says he will vote yes to self-determination if he can find a polling station that police have not closed.
"We were ordered to forgive and forget the crimes committed by fascists, like torture by the Guardia Civil, but they will come here and try and stop the referendum," he said.
Madrid fights back
The Spanish Government in Madrid has mobilised the paramilitary police force the Guardia Civil to seize ballot papers and stop schools and public buildings hosting polling stations.
Many in Barcelona, the capital of Catalonia, still associate the Guardia Civil with Franco's fascist dictatorship when they were the shock troops to crush separatism. So many have been brought in from other provinces that the Government has hired cruise ships to house them.
Madrid has also asserted direct control over the regional police force, the Mosso d'Esquadra, formed after Catalonia was granted limited autonomy in 1979. But the regional Parliament says it will not yield control of its police to the Interior Ministry and it is unclear how enthusiastically Mossos will follow Madrid's orders.
The regional president, Carles Puigdemont, the driving figure behind the referendum, said Madrid was trying to crush democracy.
"In stark contrast to the governments of Canada or Britain, Madrid has refused to accept this democratic challenge, and has opted instead for the path of authoritarian repression," he wrote in a recent article.
"In most parts of the developed world, police protect ballot boxes, polling stations and voters. In Catalonia today, the situation is the opposite."
He also accused Madrid of jeopardising the fight against terrorism just five weeks after a car driven by a jihadist killed 13 people in the centre of Barcelona, including an Australian child.
"Instead of working to prevent possible attacks, Spain's police forces are working to prevent the exercise of democracy.
This is profoundly irresponsible," he said.
'Irresponsible' move against constitution
Spain's conservative Prime Minister Mariano Rajoy has insisted the regional government is irresponsible for trying to hold an illegal referendum. Spain's Constitutional Court has ruled the referendum is in breach of the 1978 constitution that restored democracy to Spain.
Catalonia is one of Spain's largest regions with 7.5 million people. It's also perhaps it most prosperous, with a healthy economy generating nearly a fifth of Spain's income, according to local authorities.
The capital Barcelona had 32 million tourists last year. Mr Puigdemont and other local politicians have long complained that Catalonia pays far more in tax than it receives in benefits and subsidises poorer economies down south.
But there is also a strong undercurrent of Catalan nationalism in the independence movement, even feelings of superiority.
The Catalan language, mixing elements of Castilian Spanish and French, is almost incomprehensible to other Spanish speakers.
Catalonia boasts a very different culture to the bullfighting-flamenco-paella image of Spain that was promoted during the Franco years, when the fascists tried to suppress all regional differences.
Many Catalans see themselves as more innovative and entrepreneurial than other regions dominated by rich land-owning families.
Young and old united
Even for young people, the history of repression during the dictatorship — and Madrid's failure to bring anyone to justice — continues to colour feelings of national unity.
Clara Ballart is a 21-year-old student and volunteer for the independence campaign.
"Franco ordered the execution of Lluis Companys, the then president of Catalonia," she said.
"But no one will revise history to state that he was killed illegally. Nothing has been revised. Everything needs to be swept under the carpet.
"This is unreal to us. In the world we have been born into, we see places in the world that have addressed their war crimes."
Despite the presence of so many national police in Barcelona, she said her generation was no longer intimidated by the power of Madrid.
"I wasn't raised with this narrative that we are being crushed or oppressed. We are not as afraid as our parents and grandparents who were so close to that time. They could not see there was a potential for change."
A passionate minority
The passions of independistas was on display on September 11 when nearly one million people marched in Barcelona on Catalonia's national day, turning the streets into a sea of independence flags.
Yet opinion polls have consistently shown them to be in a minority, with about 44 per cent backing separation from Spain.
The Socialist Party of Catalonia is as vehemently opposed to the referendum as their conservative opponents in Madrid.
"We think it's good for Catalans to be part of Spain and part of Europe because not being part of Spain means not being part of Europe," party secretary Salvador Illa said.
"We think the right way to solve the situation in Catalonia is not to declare independence but to reach a new agreement between Catalonia and Spain, so this is our proposal.
"Any democracy needs to have the rule of law in a principle, and to break the rule of law is a very bad thing, so we do not support them in this attempt to break the rule of law and in fact we ask them to call off the referendum this Sunday."
The irony is that if Madrid had approved a referendum, the secessionists would have almost certainly lost. But the heavy-handed response has inflamed secessionist feelings and prevented any no case being argued.
The people most likely to brave police crackdowns and find polling stations on Sunday are the hard-core independistas. It is likely to be a very small turnout but with an overwhelming vote for yes. And the regional Parliament has said it will declare independence within 48 hours of a yes vote.
The thousands of foreign tourists exploring Barcelona on sightseeing buses and queueing outside Sagrada Familia this weekend may not be aware that they are about to witness a dangerous and unpredictable moment in Spanish history.