ARLINGTON COUNTY, Va. (DC News Now) — If you’re in Arlington or D.C. on Oct. 29, chances are pretty good you’ll spot more than a few Marines in the streets…along with more than 30,000 runners.

The Marine Corps Marathon will bring participants and supporters to the area, and it means there will be a lot of road closures, making it tricky to get around parts of the DMV.

The race, itself, begins at 8 a.m. on Sunday.

D.C. will have road closures along major thoroughfares, including Constitution and Wisconsin avenues NW.

Arlington will see closures along roadways including Fort Myer Drive, Richmond Highway, I-395 and Crystal Drive.

The Key Bridge and Memorial Bridge, which connect Virginia to the District, also will be closed for part of the day.

To help people improve transportation on race day, WMATA is starting Metro train service two hours early.

Among the tens of thousands of people who will be running is a Marine veteran and Purple Heart recipient who lost his arm and leg in an IED blast in the Afghanistan withdrawal. He’s helping his gym which helps people with disabilities.