The Lansing & St. Johns Electric Railroad ran north from Lansing, MI through DeWitt, MI ending in St. Johns, MI, a total of less than 30 miles. It existed from about 1900 - 1930. Although primarily a passenger line, it did carry light freight and mail, as well as some agricultural and manufacturing goods during its life. It was later purchased by the Michigan Electric Railway company.
Today, some of the right-of-way can be followed, as it now serves as the right-of-way for power transmission.
There is a book written about it, Great Northern Ghost, by Ford Stevens Ceasar.
Thanks to Jerry Fust for contributing information about this route.