Could God (if he wants) create a mountain that tall?

I assume, in theory, God could be able to create a mountain (if he wants to). I don't want to assume he wants to do it, it's just a speculation. If this mountain is tall enough, no people will be ever able to reach the summit. What if we use planes? Well, God can decide to make that mountain even higher that no planes or any kind of spaceship can see the top of it. Can God go even further and create a mountain so high that even God himself, starting from the base, cannot climb all the way to the top?