Boston Mayor Marty Walsh said he expects about 30,000 runners to participate in the Marathon and about a half-million people will cheer them all on from Hopkinton to Copley Square and everywhere in between the 26.2-mile route.
To keep everyone safe there will be thousands of police officers along the route and a surveillance booth from the ground and sky.
One thing police said they were concerned about is the possibility of vehicles being used as weapons after several attacks overseas.
So, Boston has a fleet of plows and trucks as barricades along some of the more crowded spots.
“I don’t want to get people alarmed,” Boston police Commissioner William Evans said. “There’s no intelligence, but we live in a new world where there are these things that we have to take into consideration.”
Spectators watching the Marathon are reminded that several items are banned including:
Weapons & fireworks
No backpacks, handbags or suitcases
No large blankets or sleeping bags
No coolers, glass or containers larger than one liter