A canoe travels upside down on a roof rack, resting on its gunwales, and the key is strapping it so it cannot slide or lift. Canoes are long and catch a lot of wind, so bow and stern lines are not optional at highway speed. This guide covers loading, gunwale strapping, and safe tie-down.
Pro tip: Install cheap under-hood anchor loops so you always have a solid front tie-down point.
Watch out: Never carry a canoe right side up on the highway. Upside down on the gunwales is stronger and sheds wind.