Federal agents will be on watch, D.C. police will be in full force, and Metro trains will run every few minutes to accommodate the 500,000 people that could descend on downtown Washington this weekend for the March for Our Lives rally, Mayor Muriel E. Bowser said Tuesday.

Because the Saturday march — an anti-gun-violence demonstration led by the survivors of the Parkland, Fla., school shooting — will draw thousands of students, many of them under 18, officials said they will take extra care to ensure the safety of protesters.

Medical tents staffed by volunteers will double as reunification points for groups that get separated. Water will be available. Food trucks will line up nearby.

“As the young men and women from Parkland, Florida, have been preparing for Saturday’s event, the District has been preparing to keep them safe here in Washington,” Bowser (D) said during a news conference. “We are very much looking forward to supporting this rally.”

The mayor has been vocal about her support for the mission of the march: to condemn gun violence and call for increased safety regulations.

Earlier this week, Bowser appeared in a video posted to Justin Timberlake’s social media accounts wearing a T-shirt with the outline of the District and the words “the 51st state.”

In the video, the mayor and the pop singer promoted the march’s website and smartphone app and encouraged others to participate.

“Will you march?” Timberlake asked.

“I will,” Bowser replied. “And we all need to demand action to save lives.”

On Tuesday, the mayor said the District has long advocated “common-sense gun control” and blamed federal lawmakers for interfering in the District’s ability to regulate firearms on its own terms.

Last year, the U.S. Court of Appeals for the District of Columbia struck down the District’s requirement that people seeking licenses to carry a concealed weapon must demonstrate “good reason” to carry a gun in public. The city did not appeal the decision to the Supreme Court.

“We have been really focused on common-sense gun control in our city for a long time. We deal with the impact of guns in our city every day,” Bowser said. “On a federal level, Congress has to act. I couldn’t agree more with these students.”

Students from D.C.-area schools will speak at the rally, where no featured speaker will be older than 18, according to Deena Katz, president of March for Our Lives and a television producer who also helps run a Women’s March chapter in Los Angeles.

The march itself will take participants down Pennsylvania Avenue NW from 12th Street to Third Street. Katz cautioned that the event might be less of a march than a rally, given the expected crowd size.

A main stage near Pennsylvania Avenue and Third Street NW will feature speeches from school shooting victims, D.C. students and activists.

Musical performances by artists such as Ariana Grande, whose concert last year at Britain’s Manchester Arena was the site of a terrorist attack, will be broadcast on 20 Jumbotrons along Pennsylvania Avenue.

The rally, for which 2,000 portable toilets have been reserved, begins at noon Saturday, although organizers expect many participants will begin to arrive hours earlier.

Several young organizers spearheading the march have received threats of violence since they began speaking out in public. D.C. Police Chief Peter Newsham said he wanted to assure those students they are “coming to one of the safest cities in the country.”

Newsham said no formal counterprotests have been planned.

The march will coincide with the annual cherry blossom blooms. The official start of the National Cherry Blossom Festival was moved to Sunday to mitigate congestion.

The march is being funded by a number of celebrities, including George and Amal Clooney, Steven Spielberg and Oprah Winfrey. More than 700 “sibling marches” will also take place Saturday in cities around the world, according to the organization’s website.

A school shooting at Great Mills High School in Southern Maryland gave the march renewed local significance, some officials said Tuesday, and prompted social media posts of support and solidarity from the Parkland organizers.

Parkland shooting survivor and activist Emma González, 18, tweeted early Tuesday: “We are Here for you, students of Great Mills . . . together we can stop this from ever happening again.”