Updated 5:57 p.m. | Federal and local District of Columbia officials are bracing for the hundreds of thousands of people expected to visit D.C. during the first leg of Pope Francis’ visit to the U.S.

At a news conference Thursday afternoon, security officials likened the event to a presidential inauguration, and transportation officials said there will be a number of road closures in effect. Congressional staffers and visitors will face a series of closures when the pontiff heads to the Capitol on Sept. 24 to address a joint meeting of Congress.

District Department of Transportation Director Leif Dormsjo said Independence Avenue will be closed that morning, from Second Street Southwest to Third Street Southeast. Constitution Avenue will also be closed from Third Street Northeast to Second Street Southwest.

On Thursday evening, law enforcement and public safety officials released a complete list of closures for the pope’s visit. Seventeen streets streets surrounding the Capitol complex will be closed for the pope’s address during three different blocks of time.

From 5 p.m. on Sept. 23 to 4 p.m. on Sept. 24, the following roads will be closed:

-Maryland Avenue SW between 3rd and 1st Streets SW
-Pennsylvania Avenue NW between 3rd and 1st Streets SW

In addition to Constitution and Independence Avenues being closed from midnight on the 24th until noon that day, the following roads will also be closed:

-3rd Street NE/SE between D Street SW and C Street NW Independence Avenues
-D Street NE/NW between 2nd Street NE and New Jersey Avenue NW
-First Street NE/SE between Massachusetts Avenue NE and D Street SE
-Delaware Avenue NE between Columbus Circle NE and Constitution Avenue NE
-North Capitol Street NE/NW between E Street and Louisiana Avenue NW
-New Jersey Avenue NW between D Street NW and Constitution Avenue NW
-South Capitol Street SE/SW between E Street SE/SW and Independence Avenue SW
-C Street SE between 2nd and 3rd Streets SW
-Second Street SW between Independence Avenue SW and E Street SW
-First Street NE/SE between D Street SE and Independence Avenue SE

Beginning at midnight on Sept. 24, the following roads will also be closed until 4 p.m. that day:

-East Capitol Street NE/SE between 2nd and 1st Streets SE/SW
-Louisiana Avenue NE/NW between New Jersey and Constitution Avenues NW
-Washington Avenue SW between South Capitol Street SE/SW and Independence Avenue SW

In terms of public transit around the Capitol that day, Washington Area Metropolitan Transit Authority General Manager Jack Requa told CQ Roll Call after the news conference that transit services will be running at full capacity. Though additional shuttles will be available at the Brookland Metro stop for when the pontiff celebrates Mass at Catholic University on Sept. 23, there will not be additional shuttles at the Capitol.

“We’ll be running full service trains, bus service will be out there in full capacity,” Requa said. “And we’ll encourage people going towards the Mall, towards the Capitol, to treat it like Fourth of July: Don’t everyone go to Smithsonian. And so take advantage of the other stations, and walking; it’ll just be a lot faster to get there.”

The challenge facing transit officials is that, unlike a presidential inauguration or July 4th, the pope is not visiting on a holiday where many in D.C. are out of town. So the transit system will have to contend with visitors as well as D.C. residents commuting to work.

Dormsjo encouraged D.C. residents to telecommute if they can, choose public transit over driving and to leave plenty of extra travel time. Dormsjo said DDOT estimated 70 intersections will be affected during the pope’s visit, causing a number of closures not only at the Capitol, but near the White House, Catholic University and the Naval Observatory, where Pope Francis will be staying.

In a Wednesday statement, Metro encouraged transit riders to pre-load fare cards with enough money and expect crowding on trains and at Metro stations.

“Due to crowds following Papal events, riders may need to wait extended periods of time — possibly hours — before re-entering the Metrorail system at certain stations,” Metro said. “In addition, bus customers should expect extensive detours and service adjustments as a result of events and associated road closures. All riders are encouraged to allow extra travel time during the Papal visit.”

In addition to transit concerns, security is a top concern for the high-profile event. The pope’s visit has been designated a “National Special Security Event,” meaning the U.S. Secret Service is the lead agency on planning and implementing a security plan, the FBI takes the lead on crisis response and incident investigation, and FEMA heads any emergency management.

The Secret Service will also be coordinating with the Metropolitan Police Department and other law enforcement agencies throughout the District, including at the Capitol. “It’s sort of a whole government approach overview,” Secret Service Special Agent in Charge James Murray told CQ Roll Call after the press conference. “But certainly Capitol Police has a very significant role at the Capitol.”

The Secret Service and the D.C. government will also work to keep the public informed about the visit’s implications. D.C. Mayor Muriel Bowser said the government will unveil a website on the visit on Monday. And the Secret Service launched a revamped website on Thursday, in addition to a mobile app, which Director Joseph Clancy said will be used to provide information about the pontiff’s visit.

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