This year's marathon will bring the usual challenges for those trying to get in, get out or avoid it altogether.

Unlike last year, however, the race won't be sharing the day with the University of Pittsburgh commencement and a Penguins playoff game.

Pitt's graduation is over with; the Penguins, well, you know that story. And the Pirates will be out of town.

But there will be obstacles for those trying to drive, park, shop, dine, worship or take a bus on Sunday. And again there is a college commencement, this time at Carnegie Mellon University.

Street closures

The barricades begin going up at 5:15 a.m. in the starting area on Liberty Avenue from Sixth Street to Commonwealth Place. As the day goes on, rolling closures will occur, with no vehicles allowed to cross the race course.

Course sections Downtown and in the Strip will close from 6 a.m. to 2 p.m., with the Smithfield Street Bridge, Smithfield Street and Sixth Avenue closing from 7 to 11 a.m. for the half-marathon; on the North Shore from 6:30 a.m. to 9:30 a.m. along the early part of the course and 7 a.m. to 2 p.m. around the finish area; West End and South Side, 6:30 to 11 a.m.; Oakland-Shadyside-South Point Breeze, 6:30 to 11:30 a.m.; and Homewood-East Liberty-Highland Park-Shadyside-Bloomfield, 7 a.m. to 1:15 p.m.

Traffic should be back to normal throughout the city by 2 p.m.

Carnegie Mellon is recommending that those attending the graduation ceremonies use Squirrel Hill Exit 74 from the Parkway East to avoid the race route. From the East End, Shadyside or East Liberty, access is possible via the Boulevard of the Allies and traveling through Schenley Park.

More information: www.pittsburghmarathon.com, click on Race Day Information then Road Closures. Also, www.cmu.edu/commencement.

Parking

Spaces will be available in some lots and garages on the North Shore near the finish line and Downtown garages near the starting line. Lots and garages will open at 4 a.m. but will start to close as early as 5:30 a.m. to accommodate race course street closures. The charge is $5 except for Rivers Casino, which is offering free parking (but all vehicle occupants must be 21 or older). There will be no shuttles from the North Shore to the starting line.

More information: www.pittsburghmarathon.com, click on Race Day Information, then Parking.

Transit

Nearly all Port Authority service will be rerouted from early morning until about 2 p.m. Most Downtown buses will run along Grant Street to Steel Plaza station or Ross Street to Mellon Green. South Hills buses will go only as far as South Hills Junction, where riders can transfer for free to the T. South Side buses will detour via Sarah Street and the Hot Metal Bridge to reach Downtown.

The 28X Airport Flyer will not serve the CMU campus. Its first stop will be at Amberson and Ellsworth avenues and it will use Grant Street rather than Liberty Avenue, Downtown. The 61 series buses will not serve Oakland but a free shuttle will take riders to Squirrel Hill for those routes. The 71 series routes will go only as far as Bellefield Avenue before detouring to reach Downtown. Brochures detailing Saturday and Sunday service changes will be posted on the authority's website.

More information: www.portauthority.org.

-- Jon Schmitz: jschmitz@post-gazette.com or 412-263-1868. Visit the PG's transportation blog, The Roundabout, at www.post-gazette.com/roundabout. Twitter: @pgtraffic

First Published: May 12, 2011, 4:00 a.m.