Ah, simple answer. You know the Karin tower? The tower which took days for Goku to climb when he was young(and the tower with a cat who gives magic/senzu beans)? Kami's palace, a place that floats directly above Karin tower is impossible to climb since it doesn't have a foundation. So Goku used his power stick to connect the top of Karin tower, to the bottom of Kami's palace, and climbed up using the stick. Until now, the stick remains in between the tower and the temple.
A model of Karin Tower. As you can see, there's a joint on the roof.
Kami's Palace. As you can see, there's a joint at the bottom.