If you have proficiency with a certain kind of vehicle (land or water), you can add your proficiency bonus to any check you make to control that kind of vehicle in difficult circumstances.

Rowboats are used on lakes and rivers. If going downstream, add the speed of the current (typically 3 miles per hour) to the speed of the vehicle. These vehicles can’t be rowed against any significant current, but they can be pulled upstream by draft animals on the shores. A rowboat weighs 100 pounds, in case adventurers carry it over land.