In Twin Ports by Trolley: The Streetcar Era in Duluth-Superior, Aaron Isaacs charts the history of the streetcar system that met the unique difficulties posed by Duluth, from the Interstate Bridge that crossed the harbor to the Incline Railway that carried travelers more than five hundred feet above Lake Superior. The book is, ultimately, a tour of the Twin Ports over time, with a wealth of maps and photographs illustrating routes and landmarks and picturing the people who made the rails hum. The streetcars are long gone from Duluth and Superior, but remnants survive if one knows where to look--and this street-level exploration points the way.