There, a woman named Heather Heyer was killed when a man drove a vehicle into a crowd of counter-demonstrators.
Meanwhile, US President Donald Trump said on Saturday he condemns "all types of racism and acts of violence", appealing for unity. "Public perception is key", he said. His Washington permit application says he expects 100 to 400 people Sunday afternoon in Lafayette Park, near the White House.
Some community activists were concerned that this year's heavy police presence could be a counterproductive overreaction.
Estimates vary on how many white nationalist protesters will show up.
Police officers in Charlottesville had put up metal barriers by Saturday morning to cut off access to downtown streets.
Hundreds of people, including left-wing activists, professors, students, and community members continued to march down the street to Lambeth Field.
With Charlottesville police widely criticized for their handling of last year's rally, D.C. authorities are vowing to prevent violence.
Jason Kessler, who helped organize last year's Charlottesville rally, is scheduled to speak to the crowd, as is David Duke, the former politician and Ku Klux Klan leader.More news: European banks plummet amid fears of exposure to Turkish debt
More news: Everton seal sensational Bernard, Yerry Mina and Andre Gomes triple swoop
More news: N'Golo Kante Equals His Best Premier League Goals Tally
Meanwhile, Vice President Mike Pence also reflects on the incidents in Charlottesville one year later.
The white nationalist rally participants - a couple dozen in all, according to estimates - gathered at a subway station in northern Virginia and traveled into the nation's capital via train before disembarking in Foggy Bottom near the George Washington University campus. Let us be in one voice and tell them that they are wrong.
On Saturday in Charlottesville, the downtown area was virtually locked down, with more than 700 officers on hand to ensure there would be no violence.
Two state police personnel - Lt. H. Jay Cullen and Trooper-Pilot Berke M.M. Bates - died in a helicopter crash responding to the scene.
A woman receives first-aid after a auto ran into a crowd of protesters in Charlottesville, Virginia, on August 12, 2017. That's what happened past year at the original "Unite the Right" rally and at a July 2017 Ku Klux Klan gathering in Charlottesville, where Klansmen were outnumbered 20-to-1. REUTERS/Lucas JacksonPolice in riot gear deploy near the statue of Civil War Confederate General Robert E. Lee, ahead of the one year anniversary of 2017 Charlottesville "Unite the Right" protests, in Charlottesville, Virginia, U.S., August 11, 2018.
The white nationalists are gathering in Washington on the first anniversary of their rally in Charlottesville, Virginia, that turned violent and led to the death of a counterprotester.
Earlier on Saturday, a group of anti-fascist protesters walked through the downtown area, holding signs with messages like "Good Night White Pride". But the day was largely free of confrontation.
Taking, as ever, to Twitter, the 45th President of the United States referred to last year's incidents as "senseless death and division" and urged the entire nation to come together as one.
"We have people coming to our city for the sole objective of spewing hate", Bowser said at a news conference Thursday. I am heartened by people who have stood up in Charlottesville and around Virginia this year, driven to engage in peaceful activism out of concern, compassion, and care.