Thousands gather to watch D.C. marathon

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WASHINGTON (CNN) -- More than 18,000 runners from across the country and 40 nations took to the streets of Washington, D.C. Sunday in the 27th annual Marine Corps Marathon.

An estimated 150,000 spectators turned out to support the racers.

The race was held just days after police arrested two men suspected in the Washington-area sniper shootings. Many spectators expressed relief that the more than three-week ordeal was over.

Michelle Strathy brought her two daughters to watch the race from the sidelines. "Schools closed for a couple of days and of course that frightens the children, so you try to talk positive. It's a relief," she told CNN. Strathy's husband was a first-time runner in the marathon.

The Marine Corps organized the marathon in 1976 to promote its commitment to physical fitness. It hosted about 1,200 runners that first year. Today, the 26.2 mile amateur race is the sixth-largest marathon in the United States, and the tenth largest worldwide.

The Marine Corps Marathon is also called the "Marathon of Monuments" because of the scenic course runners take past Washington landmarks.

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