"Right-click the rowboat to enter it. Ctrl + Right-click to disembark. You can load the boat with four objects. Load objects by carrying them and right-clicking on the boat, and unload them again by right-clicking on the sacks in the boat."
Can hold 4 objects, 2 passengers, and 1 driver (3 people total).
Can't be lifted when it contains cargo. You must unload it first.