The marathon and 10K start at 8 a.m. at Paca and Camden streets, following a 7:30 a.m. 5K start at Light and Pratt streets. The half-marathon begins at 9:30 a.m. at Pratt and Calvert streets. The marathon finishes on Pratt Street between Charles and Light streets. All race courses are scheduled to close at 3 p.m., though some roads are expected to reopen earlier as runners pass.

Closures will roll out from early morning through the afternoon. Among the affected routes are streets around Druid Hill Park and Lake Montebello, parts of Charles and North avenues, the Inner Harbor and waterfront, and routes through East Baltimore and Patterson Park. Pratt Street between Charles and Light streets closes at 9 p.m. Friday for race setup and is expected to remain shut until the event clears Saturday afternoon. A lane of southbound Light Street between Pratt and Conway streets will close starting at 10 a.m. Thursday.

Drivers should expect delays and traffic holds, although police and transportation officers may allow vehicles to cross race routes when conditions permit. Parking restrictions will apply along the courses and near the stadium complex from Friday evening into Saturday. Vehicles parked in violation may be ticketed and towed; motorists can call 311 for help locating a towed vehicle. The city says additional restrictions may be added if needed.

Commercial vehicles, including tanker trailers, will be barred from downtown and Inner Harbor areas from 2 a.m. to 4 p.m. Saturday. The limits apply on sections of Fayette, President, Light, Key Highway, Hanover, Pratt and Lombard streets. Cabs, buses and other mass-transit vehicles are exempt.

The city recommends traveling before the races begin or after 3 p.m. and encourages visitors to take public transit. Metro Subway service is expected to run normally, with free parking at stations from Owings Mills to Mondawmin. Local buses will be detoured or delayed. The Charm City Circulator’s Orange, Purple and Banner routes will be suspended from 9 a.m. to 4 p.m.; the Green route will detour, while the Cherry route will run on its regular schedule south of Henrietta Street.

The Harbor Connector will operate two routes from 10:30 a.m. to 7:30 p.m. The Inner Harbor Loop will serve Harborplace, Harbor East, Federal Hill, Fells Point and Locust Point; the Outer Harbor Loop will connect Fells Point, Locust Point and Canton Waterfront Park. Downtown travel may also be busier because several Disney on Ice performances are scheduled at CFG Bank Arena.

Residents and visitors can check the city’s interactive road-closure map for neighborhood schedules and current street impacts. Organizers and city officials advise allowing extra travel time and checking transit updates before setting out.