We assess the structure of grain shipping within the Great Lakes and St. Lawrence Seaway system. While U.S. export grain ships from the port of Duluth, Minnesota, Canadian export grain ships from several ports located on the Lower St. Lawrence Seaway. While North American export grain moving from West to East can be transported in several different ways, due to data limitations our focus in this analysis is on the so-called Saltie shipping market. While our findings are somewhat unexpected, they give us some unique insight into the nature of this crucial yet understudied transportation market.