Peninsula - a body of land that juts out from a larger land mass and which is usually surrounded by water on three sides. Isthmus - a narrow neck of land that separates two bodies of water and connects two larger land masses. Mountains - high rugged land forms that have an elevation of 2000m or more and a relief of 300m or more. Often snow capped because of the high elevation. Caldera - is the crater shaped top of a hill or a mountain which is volcanic in origin.
Hills are often the eroded remains of mountains.
Plain - is a broad, flat, or gently rolling land form with an elevation of less than 500m and a relief of less than 150m. Plateau - very similar to a plain, but with a elevation of 500m or more. Major Water Forms Rivers - water from small streams and tributaries sometimes meet to form a river. The river and its streams and tributaries are called a river system. From space or from a higher altitude river systems look like a leafless tree.