shanks' mare

noun
1.
one's own legs, especially as a means of moving from one place to another:
The only way we can get there is by shanks' mare.
Idioms
2.
ride shanks' mare, to go on foot rather than ride; walk:
It was such a delightful day that we decided to ride shanks' mare to the fair.
Also, shank's mare.
Also called shanks' pony, shank's pony.