Flanked by leaders of nearly all the city’s majority security forces, Mayor Muriel Bowser said the District of Columbia is expecting and planning for “very large numbers of people” for the inauguration of a ratings machine as the country’s highest leader.

“We prepare for the biggest number possible,” Bowser said, though she declined to estimate exactly how many Trump fans, protesters, pot smokers, rival bike groups, and anarchists will swell the city.

“We are well-prepared and ready for this inauguration,” said Brian Ebert, the special agent in-charge of the Washington Field Office for the United States Secret Service, at a press conference discussing logistics, security, and other matters related to the mega event.

City leaders estimate that it will cost around $30 million, of which $19 million has been appropriated by Congress. Bowser said that she expects that the federal government will fully reimburse the District for the remainder, as it has in the past.

In addition to MPD, U.S. Capitol Police, Park Police, and other regular police groups, there will be 5,000 National Guardsman on the ground. Another 3,000 officers from other jurisdictions will also augment MPD’s force, under the leadership of Interim Police Chief Peter Newsham, as has been the case in previous events.

While Bowser pointed to the biggest inauguration (Barack Obama’s 2009 swearing-in) for some historical context, there was little in the way of protest or discord. This time around, the National Park Service is processing permits for more than two dozen groups, while others—ranging from bikers supporting Trump to anarchists pledging to shut shit down—plan to make themselves heard without being officially sanctioned.

D.C. Director of Homeland Security said the city’s priority is on making sure that people are free to exercise their first amendment rights. Newsham echoed that sentiment and also said police will be prepared for any groups threatening to shut inauguration logistics down.

“We aren’t expecting mass arrests,” Deputy Mayor for Public Safety and Justice Kevin Donahue told DCist. “MPD is planning for the possibility … but it doesn’t mean they expect or believe it will happen.”

As for arresting those who partake in marijuana-advocacy group DCMJ’s pot giveaway, Bowser said at the press conference that it “wouldn’t be a priority.”

In order to accommodate the masses, Metro will remain open from 4 a.m. through midnight, with peak service running from opening through 9 p.m. Five stations in the downtown core, however, will be closed due to security concerns; bus routes will also be affected by the many street closures.

While there is no work scheduled, Metro General Manager Paul Wiedefeld said the agency is prepared to handle any track issues.

Bowser, meanwhile, noted that most transportation issues that arise during major events stem from visitors “not knowing how to pay and get where they’re going.” They each advised inauguration-goers to be prepared ahead of time. A special inaugural SmarTrip card is available for purchase online through January 13 that entitles riders to unlimited Metrorail and Metrobus trips on inauguration day.

The day is “also an opportunity for our city to shine,” Bowser said. “Federal Washington will be on display, but we invite the any visitors to see our neighborhoods, support our businesses, and get to know the residents of Washington, D.C.”