their bodies arent used to going up steps and rocks
Stairs go up and come down as well.
Stairs, you go up you go down but the stairs never move.
the stairs
The basement or the root cellar are often found when you go down stairs.
One little push and the Slinky will flip down the stairs.
The opposite is descend (go down the stairs).
go to the jungle and there's some stairs, go down the stairs and go in the door on the right!
Ferrets can easily navigate stairs
They probably can but, I don't think its a good idea to let them go down stairs because they might fall.
The answer to this riddle is "a staircase". Of course the staircase does not actually move up and down, but when you refer to a staircase directionally, you are either going "up the stairs" or "down the stairs". Its function in and of itself is to "go" up and down.
walk down them
Not really, no. The coordination of their front and back leg joints make it hard for them to walk down stairs like cats or dogs can. They can walk down from a step but it's much harder for them to walk down several steps at a time.