KPA forces had four possible routes in the perimeter: to the south, the pass through the city of Masan around the confluence of the Nam and Naktong rivers; another southerly route through the Naktong Bulge and into the railroad lines at Miryang; through the route into Taegu in the north; and through Kyongju in the eastern corridor. The KPA mounted a large offensive in August, simultaneously attacking all four entries into the perimeter. As a result, the Battle of Pusan Perimeter was not one single engagement, but a series of large battles fought between the UN and KPA divisions all along the perimeter.