ATHENS, Greece - The sprint to the Olympics is being run through an obstacle course.

Frantic work - including on the main stadium - slogs on in mud, through rainstorms and at night. Roads and squares are ripped up for repaving or new rail lines. Cement mixers and cranes snarl city traffic. Whirlwinds of dust spin through neighborhoods.

Ready or not, the Athens Games will start 100 days from today.

"My major challenge is the same as that faced by everybody else involved in games preparations: Stay focused and make every minute count, because we don't have a moment to lose," said chief Athens Olympics organizer Gianna Angelopoulos-Daskalaki.

Preparations for these games have been racked by delays and glitches. Four years ago, about the biggest last-minute concern officials in Sydney had was planting flowers outside arenas.

And for Athens' 4 million residents, the frustrations and burdens of living in a giant work-in-progress could get worse before the Aug. 13-29 Olympics begin.

The International Olympic Committee arrives Monday for its last major inspection visit, hoping everything comes together in the days ahead.

"We won't have much time before the games, that is for sure," Denis Oswald, the top IOC overseer of Athens' preparations, told The Associated Press. "Some time ago, we were also fearing that things would be ready only after the games. Now we are confident that everything will be finished before the games."

But just how soon before is still an open question.

Oswald and the IOC want all venues finished by the end of June. That applies even to the main stadium's new roof, whose two huge arches still must be moved into place. Attempts to glide the two sides into place could begin later this week.

Other key projects, including a new tram line, are not expected to be ready until less than a month before the opening ceremony. And progress on a roof for the swimming pool was so far behind, it was scrapped altogether.

"Our experts who have reviewed these plans say, 'Yes, it's feasible. It can be done,'" Oswald said. "But as long as it's not done, you never know if any unexpected difficulty will arise."

IOC president Jacques Rogge put Athens organizers on notice that he expects some welcome surprises during next week's visit.

"I look forward to hearing more news from them of how much is being accomplished in a short time," Rogge said.

"As we enter the final stretch together, most of the preparations are already complete," he added. "More work remains, however, and we are continuing our close cooperation ... to ensure that everything needed for the games to succeed is in place."

Early today, three bombs exploded outside a police station, but there were no reports of injuries, authorities said.

The pre-dawn blasts, which occurred within 26 minutes, came before ceremonies to mark 100 days left until the games.

An anonymous caller to an Athens newspaper warned of the attacks in advance, but gave no motive or claim of responsibility.

Some Athenians wish the IOC would just call off the whole thing.

"I do not care at all about the games. It would be better to not have them so that we could have our peace," Eftihia Liakakou said in the seaside suburb of Paleo Faliron.

Residents there staged protests and sued to stop construction of a tram line they say will restrict access to the beach.

Georgia Leilemidou, who works in a pastry shop in the same neighborhood, just wants life to get back to normal.

"It is a hassle. Athens is an endless construction site," Leilemidou said. "When will it end?"