Marathon world record holder Paula Radcliffe had to settle for second place in her first race for 21 months.
Paula was beaten by American Kara Goucher in the Great North Run in Newcastle. She hadn't been racing after having a daughter, Isla, in January.
Goucher finished 56 seconds clear in one hour, six minutes and 57 seconds to set the year's fastest half-marathon, which is 21kms long (13.1 miles).
London Marathon winner Martin Lel won the men's race by eight seconds.
Paula ,33, said afterwards: "My pride's taken a little bit of a bashing. I came out here wanting to win the race but it is good to be back."
On Saturday loads of children ran the Junior and Mini Great North Run, a shorter version of the adult course.