A cove is a small type of bay or coastal inlet. Coves usually have narrow, restricted entrances. They are often circular or oval, and are often found in a larger bay. Small, narrow, sheltered bays, inlets, creeks, or recesses in a coast are often considered coves. The term can also be used to describe a valley between two mountain ridges. Coves are formed by differential erosion. Differential erosion occurs when softer rocks are worn away faster than the harder rocks around them. These rocks further erode to form a circular bay with a narrow entrance called a cove.