DULUTH, MN (KDAL) - Marathoners can be a stubborn and driven bunch. The most-stubborn among them can attempt to tackle the Great Lakes Marathon Series. The newly-created race circuit is a collection of 25 marathons in the U.S. and Canada that take place along the great lakes, and, of course, includes Grandma's Marathon. The series has partnered with the Alliance for the Great Lakes, a citizens organization devoted to the great lakes' ecosystem and economies. The aim is to help raise awareness of conservation and restoration efforts. Runners attempting to race the circuit would receive benchmark awards at various stages, and would garner a grand prize for completing all 25 races. More information, including how to register for the circuit, can be found at www.greatlakesmarathonseries.com.