Runners pass the Lincoln Memorial at about the 10-mile mark during the 2011 Marine Corps Marathon. (Jonathan Newton/The Washington Post)

Three big events will create traffic challenges in the District this weekend: The 2013 AIDS Walk and the Howard University Homecoming Parade on Saturday, plus the Marine Corps Marathon on Sunday.

This posting will give you the D.C. street closings for all three, provided by D.C. police, plus the Arlington County street closings for the marathon, provided by Arlington police. Nearest Metro stations also are listed below. In a separate posting, we’ll have more detail on Sunday’s marathon and a map.

AIDS Walk

The staging area will be on Pennsylvania Avenue NW from 13th to 14th streets NW. These streets will be closed from 7 p.m. Friday till 2 p.m. Saturday:

• 14th Street and Pennsylvania Avenue NW
• 13th Street NW and Pennsylvania Avenue NW
• 13-1/2th Street NW and Pennsylvania Avenue NW

The walk is scheduled to start at 8:30 a.m. and end about 11 a.m., when the streets listed above should be reopened to traffic.

Route: The walk begins at 12th Street and Pennsylvania Avenue, turns east on Pennsylvania  Avenue, south on Third Street, west on D Street SW, north on 4th Street SW, west on Independence Avenue SW to 7th Street SW, east on Independence Avenue SW, north on Third Street SW and west on Pennsylvania Avenue NW to the finish line.

Metro: The closest Metrorail stations to the start are Federal Triangle and Metro Center. Metro opens at 7 a.m. on Saturday.

Howard University Homecoming Parade

The parade will stage beginning at 7 a.m. in front of the Johnson Administration Building, 2400 Sixth Street NW, on the Howard campus.

The parade will start at 10 a.m. and continue till about 12:30 p.m., when the streets along the route listed below should reopen to traffic.

Route: The parade will go north on Sixth Street NW, west on Fairmont Street NW, south on Georgia Avenue NW, southeast on Florida Avenue NW, north on Fifth Street NW, east on T Street NW to Anna Cooper Circle, southwest around the circle, north on Third Street NW, east on Elm Street NW, north on Second Street, west on Bryant Street, north on Fourth Street NW to the Valley (between College Street NW and Howard Place NW) where parade will disband.

Metro: The nearest Metrorail stations are U Street and Shaw-Howard University.

Marine Corps Marathon

The race begins at 7:55 a.m. Sunday at Arlington Cemetery, crosses the Potomac River into D.C., then returns to a finish near the Marine Corps Memorial in Arlington.

D.C. streets along the route are scheduled to close starting at 6:50 a.m. Sunday and reopen by 1:30 p.m., but the schedule may vary depending on the status of the marathon and the condition of the streets.

Route in D.C.:

• Key Bridge
• Canal Road NW from M Street NW to Reservoir Road NW
• Reservoir Road from MacArthur Boulevard NW to Canal Road
• MacArthur Boulevard from Foxhall Road NW to Reservoir Road
• Foxhall Road from Canal Road NW to MacArthur Boulevard
• M Street NW from Canal Road to Wisconsin Avenue NW
• Wisconsin Avenue from M Street NW to K Street NW
• K Street NW from Wisconsin Avenue NW to Rock Creek and Potomac Parkway
• Rock Creek and Potomac Parkway from K Street NW to Independence Avenue SW
• Memorial Bridge
• West Potomac Park
• East Potomac Park (access to Golf Course and Tennis Courts available)
• Maine Avenue SW from East Basin Drive SW to Independence Avenue SW
• Independence Avenue from Maine Avenue to Ohio Drive SW
• Ohio Drive SW between independence Avenue SW and Lincoln Circle
• Lincoln Circle from Ohio Drive SW to Henry Bacon Drive NW
• 23rd Street NW from Lincoln Circle to Constitution Avenue NW
• Constitution Avenue from Bacon Drive to 15th Street NW
• 15th Street from Constitution Avenue NW to Independence Avenue SW
• 17th Street from Constitution Avenue to Independence Avenue
• Madison Drive NW from 15th Street NW to Third Street NW
• Third Street from Pennsylvania Avenue NW to Independence Avenue.
• Pennsylvania Avenue NW from Third Street NW to East Capitol Circle
• First Street from Pennsylvania Avenue to Maryland Avenue SW
• Maryland Avenue from South Capitol Circle to Third Street SW
• Jefferson Drive SW from Third Street to 15th Street SW
• 14th Street SW from Jefferson Drive SW to the northbound HOV lanes
• HOV lanes from 14th Street SW to the HOV ramp at South Eads Street

Westbound M Street will remain open up to Wisconsin Avenue NW. Motorists must then turn north on Wisconsin Avenue from M Street or east from Wisconsin Avenue to M Street. Police say they will reopen the roadways as soon as possible, provided doing so does not interfere with the race.

Arlington County police list these street closings for the marathon:

• Eastbound Washington Boulevard will be closed at I-395 toward Memorial Bridge from 4 a.m. to 4 p.m.
• From 4 a.m. to 6 p.m., Route 110 will be closed in both directions to all traffic. North Meade Street will be closed from Fairfax Drive to Marshall Drive. There will be no access to Lynn Street or Meade Street from Route 50. North Lynn Street, from Route 50 to North 19th Street, will be closed. Ft. Meyer Drive will be closed from 19th Street to Route 50. North  Moore Street from 19th Street to Wilson Boulevard will be closed. Wilson Boulevard will be closed east of North Nash Street.
• From 4 to  9:30 a.m., Westbound Washington Boulevard from Memorial Circle to I-395 will be closed.
• From 7:15 a.m. to 11:15 a.m., Eastbound Lee Highway from Kirkwood Road to North Lynn Street will be closed. Westbound Lee Highway from N. Scott Street to Kirkwood Road will be closed to through traffic Local traffic can take Scott Street to Veitch Street. People leaving the area can use westbound Lee Highway to Spout Run and exit the area by the George Washington Parkway.
• The southbound I-395 HOV lanes from D.C. will be closed from 7:30 a.m. to 3 p.m.
• From 7:30 a.m. to 4 p.m., local traffic will be permitted in one lane on 12th Street South from Eads Street to Army Navy Drive. Police urge drivers to avoid this route, because it will be closed periodically. Use South 15th Street for access to hotels. Crystal Drive will be closed from 12th Street to 23rd Street. Rotary Road will be closed throughout Pentagon South parking. Columbia Pike will be closed at Joyce Street. Reach the Pentagon by  Boundary Channel.
• From 7:30 a.m. to 5 p.m., Army Navy Drive will be closed between Fern Street and South 12th Street.

Metro: Metrorail will open at 5 a.m. Sunday. The nearest station for the start is Pentagon. The nearest for the finish is Arlington Cemetery. (The Arlington Cemetery station won’t open till 8:30 a..m.) Rosslyn station also is within walking distance of the finish area.