Por•tage |'pôrtij|
noun
the carrying of a boat or its cargo between two navigable waters: the return journey was made much simpler by portage.
• a place at which this is necessary: a portage over the dam.
• archaic the action of carrying or transporting something.
ORIGIN late Middle English : from French, from porter "carry." The sense relating to carrying between navigable waters dates from the late 17th cent.
The length of a portage is measured in "rods." As Robert Beymer explains, "one rod equals 16 1/2 feet. Since that is roughly the length of most canoes, it is the unit of linear measurement in canoe country" (Boundary Waters Canoe Area: Western Region).
Angleworm Trail portage, the last of roughly 640 rods.