Grandma's Marathon - June. A great race on a great lake. The course for Grandma's Marathon is both scenic and fast. It starts amid the north woods just outside of Two Harbors, Minnesota and parallels the beautiful shores of Lake Superior, the world's largest freshwater lake and an impressive natural wonder. Runners savor the image of the majestic water as they race through miles of countryside and over gently rolling hills. A medley of musical entertainers along the course provide a boost for participants and volunteers. The route parts from the water's edge and runners make their way through the historic Duluth downtown as the journey nears an end. The finish line is in Canal Park (one of Minnesota's top visitor attractions) – site of quaint shops and restaurants, the famous Aerial Lift Bridge, and, once again, the glorious waterfront.