When William Butler Ogden contemplated building the first railroad out of Chicago to Galena, he wanted to reach Elgin on the Fox River first. From there he needed a right of way with easy grades to Rockford and on to Galena.  His surveyors found that, beyond Elgin, a fairly easy grade could be found at a small gap in the Marengo Ridge.  Ogden went out to the small community of Marengo located along the Chicago-Galena Road and asked well-to-do locals to help fund the Galena and Chicago Union Railroad construction through the area.  He had some success. With that, construction crews laid rails through Marengo on the way to Belvidere and Rockford by 1851.  This line would change the economic face of the area from that time until now.  That is the story that Craig Pfannkuche, Archivist for the Chicago and North Western Historical Society, will tell.