DULUTH, MN (KDAL) - There are over 17 thousand runners signed up for the various races during Grandma's Marathon weekend in Duluth. When family and friends are included, officials expect upwards of 50 thousand people to be in the area with an economic impact of 8 and a half million dollars for the region. Racing begins on Friday afternoon with the Whippersnapper Races for kids at Bayfront Park. The WIlliam Irvin 5-K starts at 6 p-m followed by entertainment under the "Big Top" in Canal Park. On Saturday the USA Men's and Women's Half Marathon Championships get underway at 6:15 and 6:25 respectively, followed by the Garry Bjorklund Half Marathon start at 6:45. Grandma's Marathon begins at 7:45. Race details can be found at grandmasmarathon.com.