Second annual Merrell Down & Dirty National Mud and Obstacle Series.

Thousands came out Sunday to to get dirty during the Merrill Down and Dirty Race National Mud and Obstacles Series at the Georgia International Horse Park. Participants ran a 5K or 10K and there was a 100-yard dash and 1-mile race for children. A portion of the proceeds from the race will benefit "Operation Gratitude," which will send care packages to troops overseas.