The Colsac III, the ferry carrying travelers and their vehicles across the Wisconsin River between Columbia and Sauk counties at Merrimac, closed for the winter season Thursday due to ice on the river.

The Colsac III, which runs free of charge 24 hours a day in season as part of Highway 113, began 2008 operations April 2.

Colsac III is Wisconsin's only free ferry. The craft holds 15 vehicles at a time, in addition to bicycles and pedestrians. A single crossing takes about seven minutes. Passengers board the ferry at Okee on the south bank of river and Merrimac on the north bank.

The ferry will resume operations in the spring when the river becomes free of ice.

The ferry has operated free of charge since 1933. Prior to that, private toll ferries were used dating back to 1844.