I show that in Physics 6, Aristotle presents a theory of the metaphysics of natural continua. I argue that this theory is a revision of an older view found in Physics 3-4 on which time and change are said to be continuous because magnitude is so, while in 6, Aristotle argues that changing bodies are the basis for the continuity of everything else. I discuss several longstanding problems in the interpretation of the Physics including: the dynamics of continuous changes between contradictory states, instantaneous changes, and the divisibility of change.