The Merrimac Ferry connects the Wisconsin River from the northern extremity of State Highway 113 in Columbia County to the southern extremity of State Highway 113 in Sauk County. The Merrimac is one of the last of over 500 ferries that once crossed Wisconsin’s rivers and lakes. A ferryboat trip across the river is available 24 hours a day, 7 days a week, and is Wisconsin’s only free ferry. The ferry line operates for most of the year; it is operational until the Wisconsin River begins to freeze during the winter months.

This ferry line began in 1844, 4 years before Wisconsin’s statehood. It was not until 1924, however, that the present type of cable-operated ferryboat came to be used. The Wisconsin State Highway Commission assumed responsibility for the operation of the Ferry in 1933; up until that year the Ferry had either been privately owned or owned by Sauk County and Columbia County. It was in 1933 that the Ferry became free. The boat currently used for the Merrimac Ferry is the Colsac III, the successor of Colsac I and II. The ferry name is a phonetic combination of the two counties the ferry line connects.