Honolulu Marathon officials are advising those attending the 10 p.m. Garth Brooks concert Saturday at Blaisdell Arena not to linger too long after the event, especially if they park along Kapiolani Boulevard.

The nearly sold-out concert is scheduled to run until 12:30 a.m. Sunday, and Kapiolani Boulevard is expected to be shut down for that day’s 44th running of the marathon at 1 a.m., city and marathon officials said during a news conference on race logistics Thursday.

“It’s scheduled to be a 2-1/2-hour concert which is scheduled to end very close to 1 a.m.,” said Rick Taniguchi, marathon managing director. So those parked along Kapiolani Boulevard, in particular, “need to expeditiously get to their vehicle and remove them prior to implementation of our road closure,” he said.

Drivers parking anywhere on the race course risk having their vehicles towed, Taniguchi said.

Because the 10 p.m. concert is being preceded by a 6:30 p.m. show, also by Brooks and wife Trisha Yearwood, Blaisdell crews will need to hurry through a cleanup of the arena between shows, which might push back the start time of the later event, he said.

One of two parking lot exits also spills out onto Kapiolani Boulevard, so those who depart late may be able to exit only from the South King Street side.

Mark Garrity, acting director of the city Department of Transportation Services, said motorists who park along any portion of the 26-mile route should remove their vehicles by 1 a.m. Sunday at the latest.

Affected areas include downtown Honolulu, Ala Moana, Waikiki, Kapiolani Park and Kahala, and from East Honolulu to Hawaii Kai. Honolulu Police Department Maj. Gordon Gomes said lane and full street closures will be implemented as needed. Go to honolulumarathon.org for more road closure information. The public can also call the race-day, traffic-only hotline at 792-6630.

The regular schedule for TheBus will be maintained, although some modifications to routes will need to be made to accommodate the marathon, he said. “So please allow extra time to use TheBus on Sunday morning,” he said.

Extra bus service will be provided this year from Kapiolani Park to the Ala Moana end of Waikiki from about 9 a.m. to 1:30 p.m. for runners and supporters.