Climb up and climb down:You climb up the staircase and climb down the stair case. You climb up a tree and climb down a tree.
For example: The monkey climbed up the tree within a second.
As the lift was not functioning , I was forced to climb down the staircase .
If you want to be fit, avoid taking the lift and climb up the stairs.
Raj climbed up the mango tree to pluck some mangoes.