It was here, at the corner of Fourth and Water streets, where the Charlottesville that once was ended and the Charlottesville of today began. A car plowed into a crowd of people. A young woman was killed. And another painful examination of racism in America was underway, one with Charlottesville as its focus.

That focus once again settled on the college town this weekend, on the first anniversary of the largest white-supremacist rally in decades.

The intersection, in a way, was a distillation of a country and city still reckoning with the racism in its past and present.

There were more than 100 mostly young protesters, some who had come from other states, calling for an end to white supremacist groups. There was an overwhelming police presence that some demonstrators called symptomatic of an over-policing of minority communities in America.

And there was a mother who had come to the exact spot where her daughter, Heather Heyer, was killed last year when a car, allegedly driven by a man who police say identified himself as a neo-Nazi, plowed into a crowd.

Beside the makeshift memorial swelling with flowers and posters, Susan Bro tried to put into words the tensions that not only were at the root of her daughter’s death but that also infused a service in her memory on Sunday.

“We have a huge racial problem in our city and in our country,” she said. “We have got to fix this, or we’ll be right back here in no time.” She added: “I think last year’s eruption — that infection gives us a little better understanding of how bad it is so that we can gradually, slowly and difficultly heal.”

On the other side of the barricade, there was less a feeling of reconciliation than anger, as protesters screamed at police officers, whom some demonstrators had all weekend tried to associate with racism and fascism.

The night before, protesters had gathered at the steps of the Rotunda at the University of Virginia, before a giant banner that said, “Last year they came with torches; this year they come with badges,” and then marched through the streets for hours. On Sunday, the protesters, who had come out to combat absent white supremacists, were trying to combat the police, too. They cursed them. Insulted their looks. “Blue lives don’t matter,” the crowd chanted. And: “We don’t need cops.”

The year before, police and authorities in Charlottesville had been so outnumbered and ill-prepared for the white-nationalist “Unite the Right” rally that surged through Charlottesville’s streets that an independent report later commissioned by the city largely attributed the “disastrous results” to the police. Two Virginia State Police troopers in a helicopter also died in a crash last year while monitoring the civil unrest.

In a city already divided over race, and over whether the old Charlottesville could ever be reclaimed, the contrast between last year’s police presence and this year’s became another polarizing issue.

Some called the heavy law enforcement presence a difficult necessity to ensure everyone was safe. Others said the police made them feel anything but safe. And still others saw a racial disparity in the display.

“I was here last year and was almost hit by the car,” resident Zoe Spellman, 31, said. “It’s sad that our relationship with the police is manifesting itself this way. I saw last year how they would not help us. We begged for help on [August] the 11th. We begged for help on the 12th. . . . And for we white people, this was the first time we felt what black people must feel all the time.”

Another resident, Cindy Lou Heinemann, stood on the other side of the barrier holding a sign that proclaimed her support for the police. She said she had never blamed the police for what happened last year. It was the clashes that killed Heyer, not the police. And now, with the police being criticized again, she said she felt compelled to come down.

“This does not represent the city by any means,” she said of the anti-fascist protesters. “This is not a black or white person thing anymore — this is just ugly.”

Police said that they were aware of the consternation that their strong presence has elicited among some protesters but that it was necessary.

“We are trying to maintain order and have a duty and obligation to try to make sure there is no property damage,” Charlottesville police spokesman Tony Newberry said. “We’re here to protect the different groups who have come here to voice their First Amendment rights.”

Where many people wanted to voice their rights was at the intersection, where there were several long and tense standoffs between police and protesters. There was at least one skirmish, just before 2 p.m., leading to an arrest, amid screams and even more tension. The charge will likely involve disorderly conduct or trespassing, Newberry said. It was one of two arrests on Sunday; the other was for blocking traffic.

Behind the intersection was a pedestrian mall, normally humming with weekend shoppers and restaurant-goers. But many shops were closed. The ones that were open might as well not have been.

At the end of one barricaded alley, and down the steps, a store clerk named Jinny Cowgill looked over an empty vintage store and chatted with a friend on Saturday. It was getting on toward noon, and normally by that time, customers would be coming and going, but the store hadn’t seen a single shopper.

“You’ve heard of food deserts — this is like a business desert,” said the friend, Carolyn Burgess. “ . . . Last year, we were terrorized by the KKK, and this year we’re terrorized by the police.”

“It’s a great line,” replied Cowgill. “But I don’t feel terrorized.”

“I feel like we’re under martial law,” Burgess said.

A few blocks away on Sunday, Karen Walker stood outside her empty flower shop on Fourth Street, a short distance from the Heyer memorial.

“Come here,” she said. “I’ll show you something.”

Inside the flower shop — where bundles of flowers were everywhere, and gentle music played — was a big picture window in the back, through which she watched 10 police officers sitting in an alley behind her shop, in riot gear.

“And this is my office view,” she said. “This is a flower shop. We’re inside here preparing flowers for happy events.”

And outside, at the intersection that had changed the city, steps outside her door, there was everything else.