He exited from one pot out of another identical pot outside the gates of Azkaban. Immediately he was welcomed by the sound of the wind howling angrily, whipping itself to a fury. Beneath his feet, Albus could see the sea foaming and crash on the jagged spires of rockface below. However, it was above, in the sky, where the most daunting sight presented itself. A swirling grey river of shrieking dementors circled the stone castle. They moved listlessly, ignoring Albus's presence; it was not his soul they were interested in. With an awkward creak, the gates opened by themselves. They were enchanted to do this. They did not need to remain locked as the dementors stopped any prisoners from leaving.