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Beach is an accumulation of sand, pebbles, or small rocks along a shoreline. These materials may be supplied by streams, worn away from sea cliffs, or washed up from shallow sea bottoms. Waves and currents give beaches a variety of shapes. For example, pocket beaches (Halfmoon Bay, California) have a curved shape and are usually bordered by hills. Spits and hooks (Sandy Hook, New Jersey) stretch out into the water in the shape of a finger or hook. Sedimentary capes (Cape Canaveral, Florida) also extend into the water but are broader than spits and hooks. A beach may also be a sandy stretch that connects islands with a mainland (Marblehead, Massachusetts). Waves along low coasts may build barrier beaches (Miami Beach, Florida). Barrier beaches run parallel to the coastline and are separated from the mainland by a sound or lagoon. Beaches are popular recreational spots. Well-known beach resort areas include the Riviera on the Mediterranean coasts of southern France and northern Italy, and the coasts of Florida, California, and Hawaii in the United States.
 Coastal plain is a stretch of lowland along a seacoast, which slopes gently toward the sea. In many cases, such a plain may be an elevated part of the ocean floor. Solid materials carried off by rivers or waves form other coastal plains. These materials are deposited along the shore, extending the coast seaward. The Atlantic Coastal Plain is a good example of a fertile and well-populated coastal plain. It lies along the eastern shore of North America from Canada to Florida. A zone called the Fall Line divides this low plain from the higher plateau known as the Piedmont. Along the Fall Line, waterfalls and rapids tumble from the plateau to the plain. Coastal plains generally have few and poor harbors. But the mouths of rivers along the Atlantic seacoast have produced some fine harbors. Flood plain is the floor of a river valley, beyond the riverbed. A flood plain is formed of mud, sand, and silt left by the overflow of a river. These materials are carried off by the river as it erodes (wears away) the land upstream. A river in flood can carry a large amount of eroded material, which the overflow waters deposit onto the flood plain.
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