Water and wind gaps are transverse erosional cuts through higher elevations. These features are abundant in the Appalachian Mountains, and several of them are briefly described. What they all have in common is the inability of actualists to offer a viable hypothesis for their formation. The common antecedent and superimposed stream hypotheses do not explain the observations. However, both water and wind gaps can be explained by the channelized flow phase during the runoff of the Floodwater from the Appalachians.