Runners will lace up their shoes to compete in the Boston Marathon.
This year, there will be extra security to keep the runners and spectators safe during this celebratory event.
The enhanced security presence has more than doubled the amount from last year after two bombs went off which killed 3 people and injured around 260.
Authorities say they want to keep a balance between the excitement and the traditional feel of the marathon along with tightening their security in response to last year's terrorist attack.
“You know if it’s a stadium you can wand people going into a stadium, you can check bags... 26.2 miles is quite a lot of yardage to cover and secure it but I think we have a great plan to do it," Boston Police Commissioner Bill Evans said.
There's an estimated 36,000 athletes that will be running in this year's event.