The free Murray River and lake punts, run by the state on a cable, and SeaLink's paid crossing to Kangaroo Island.
South Australia's Department for Infrastructure and Transport runs the ferries that carry traffic across the River Murray, and none of them charges a fare. They are cable ferries hauled between two ramps, working day and night with no timetable, so the useful question is never when the next boat leaves. What matters is whether the crossing is open, and the state publishes a time-stamped status table with one row for each landing and a column for closures and restrictions.
Walker Flat, Purnong, Tailem Bend and Wellington sit below Lock 1, with Narrung out between the lakes, while Cadell and Morgan belong to the stretch the state's table files as above it, and the crossings tend to stop for different reasons. At Walker Flat and Purnong the risk is the river itself: closures are judged against Australian Height Datum levels, the last big flood shut both through a whole summer, and afterwards a council weight limit on Purnong's approach roads kept heavy vehicles off for months while Walker Flat reopened to all traffic. At Tailem Bend the ferry Dotterel is most exposed to high wind, and it also comes out of service in daylight for scheduled cable replacement. Each page names the bridge or neighbouring ferry to use instead.
Kangaroo Island works on entirely different terms. SeaLink's ferry across Backstairs Passage from Cape Jervis to Penneshaw is a commercial service of about 45 minutes, with fares that vary by sailing and demand and a check-in 30 minutes before departure.