MITROVICA, Kosovo -- A high barrier of sticks and stones blocks the main bridge over the Ibar River -- put there by ethnic Serbs as a bulwark against their ethnic Albanian neighbors who live just a short walk away on the other side and, in theory at least, share the same territory, Kosovo.
But five years after Kosovo declared independence -- carved from Serbia with the help of NATO's intervention in 1999 -- the minority Serbs who live here in northern Kosovo eke out parallel but separate lives, doggedly rejecting Kosovo's sovereignty and pretending in every possible way the new country does not exist.
Serbian flags flutter proudly. The epic battles described in history texts and the folk music wafting from crowded cafes reflect the preferences and prejudices of Serbia. Only a small minority of northern Serbs ever set foot in Pristina, Kosovo's capital, just an hour's drive away. Those who do go say they are afraid to tell their friends.
Now, however, after a landmark power-sharing accord in April between Kosovo and Serbia, Serbs here will find it harder to ignore Kosovo's independence. Under the agreement, the police and courts are supposed to obey Kosovo law, Serbian judicial structures are to be eliminated and public sector salaries will be paid by Pristina rather than Belgrade.
In return, Serbian municipal structures will retain autonomy over matters like health, education and culture, though Kosovo wants to put its stamp on all university diplomas. The two countries also have until Saturday to make progress in the effort to identify missing people from the brutal 1998-1999 war that pushed forces loyal to Slobodan Milosevic, the former Serbian strongman, from this region, where corners like this one are still predominantly Serb.
While the agreement stops short of Serbs recognizing Kosovo's independence, it has been hailed by the European Union, which brokered it, as a breakthrough that can help overcome ethnic enmities, bring regional stability, enhance economic development in two of Europe's poorest countries and help clear the way for them to join the union.
But how life is lived day to day by Kosovo's ethnic Serbian and Albanian neighbors in places like Mitrovica makes clear the enormous challenges that threaten to unhinge Brussels' lofty ambitions. Chief among them is the need to win the hearts and minds of the 50,000 decidedly recalcitrant Serbs in northern Kosovo, some of whom are vowing to resist or flee if the deal is put in place.
In a sign of the obstacles ahead, one senior administrator in the offices here granting Kosovo identification cards was shot in the leg late last year, while hand grenades have been lobbed at staff members' homes.
Already, Serb leaders are calling to boycott municipal elections that the agreement foresees by the end of October. Others say they feel betrayed by Serbia, Kosovo and Europe and will barricade and boycott the new institutions, pull their children out of school or sell their homes.
"We are part of Serbia; we don't have the flag of Albania here," said Dragisa Milovic, a member of a Serbian nationalist party who is mayor of Zvecan, a town in the north. "I will never allow my son to get a diploma with the Republic of Kosovo on it. I will be the first person to leave."
Nevertheless, Adriana Hodzic, head of the Mitrovica North Administrative Office, said 7,000 people from the predominantly Serb area had acquired Kosovo identification documents like car licenses or business registrations since last September -- a hopeful sign of grudging acceptance.
The agreement was signed on to by two former sworn enemies, Prime Minister Hashim Thaci of Kosovo, a guerrilla commander of the Kosovo Liberation Army, and Prime Minister Ivica Dacic of Serbia, a wartime spokesman of Mr. Milosevic, the former Serbian leader. Mr. Thaci acknowledged in an interview that the deal represented a psychological challenge for both Serbs and Albanians to accept but insisted that reconciliation would triumph.
"People are not used to peaceful agreements between Serbs and Kosovars," he said. "They are used to violence and conflicts between our two countries. But implementing this deal is unstoppable and I am optimistic for the future. We are all Kosovars."
Despite the initial optimism, the agreement faces considerable hurdles.
Georgios Makeroufas, political adviser to the European Union's rule of law mission in northern Kosovo, noted that the ethnic Serbs would invariably come under enormous social pressure to boycott the new institutions. Moreover, Serbs who worked for the police and the courts in the north drew salaries from both Pristina and Belgrade, and would lose one salary when Serbian institutions were dissolved. Those who refused to join the new Kosovo police force and courts would lose their jobs, making them potential "spoilers" for the agreement.
"We are trying to extend Pristina's authority in a place where citizens see the Kosovo state as an enemy rather than a friend," he said. "It is not a given that Serbs in the north will integrate."
Here in Mitrovica, long an ethnic hot spot in relations between Serbs and Albanians, few outwardly support the deal, including among the younger generation for whom the memory of war remains remarkably visceral.
Marko Jaksic, 29, a lawyer who works as a clerk in a Serbian high court in Mitrovica and also writes an influential blog, said he would rather work as a street cleaner than join a court under Kosovo's jurisdiction. He said that a majority of judges and prosecutors at his court planned to ask to be transferred to Belgrade.
"I am living with Albanians for nearly 30 years and I don't trust them," Mr. Jaksic said, noting that he was too afraid to set foot in Pristina and had no Albanian friends. "If Kosovo laws are our laws, then my future grandchildren will be citizens of a state I don't recognize, and I cannot accept that."
Elsewhere in Kosovo, resistance to the deal is also strong, and the Kosovo opposition movement Vetevendosje -- "self-determination" in Albanian -- said it planned mass demonstrations to show its discontent.
Glauk Konjufca, a senior member of Vetevendosje who is also in the Kosovo Parliament, said the agreement threatened to create a de facto state within a state. He argued that giving further autonomy to Kosovo's Serbs would effectively transform Kosovo into "another Bosnia," where lingering ethnic nationalism has paralyzed the country's progress.
Yet for all the griping on both sides, some here are also optimistic that the agreement could end the north's isolation. European Union officials say that eliminating parallel judicial structures for Albanians and Serbs will also help alleviate a security vacuum that is being exploited by criminals.
Above all, supporters of the deal, like Rada Trajkovic, a Serbian doctor who is one of a small number of Serbs in the Kosovo Parliament, said she hoped it would overcome the ethnic divide. Her clinic in a Serbian enclave in southern Kosovo spills over with Albanian and Serb patients who mingle comfortably. She speaks Serbian in the Parliament.
"My hope is that people can start living a normal life," she said. In the meantime, she added, she does not venture into Mitrovica at night to avoid being harassed by hard-liners.
This article originally appeared in The New York Times.