This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated.

45,000 runners and more than a million spectators are expected at this year’s Chicago Marathon.

The setup is already underway and security is top of the list or priorities.

As the final touches are put onto the start and finish lines at Grant Park, the lessons learned from the Boston Marathon bombings nearly 6 months to the day of Chicago’s race were revealed Tuesday.

Chicago police, emergency management, US secret service, FBI and homeland security are among the many departments who’ve stepped up restrictions and enforcement for Sunday’s race.

No large bags or backpacks will be allowed.  Instead, runners will get a clear plastic bag to hold items when they check in.

Unlike past years, runners cannot leave unattended bags at Grant Park or anywhere along the route.

And spectators will not be allowed to join a runner on the course as it winds through 29 Chicago neighborhoods.

And for the first time, only registered runners and ticket holders will be allowed at the start and finish lines.

And even though there’s no known threats to Chicago or the marathon, explosives detection teams from local and federal agencies will out along the entire course, including bomb sniffing dogs.

Undercover officers will be in the crowd and video surveillance will be used.