• A hill is a piece of land that rises higher than everything surrounding it. It looks like a little bump in the Earth. Since theyre higher than everything around them, hills are good places to get a nice view.

    Hills are easier to climb than mountains. They are less steep and not as high. But, like a mountain, a hill will usually have an obvious summit, which is its highest point.

    According to the U.S. Geological Survey, there is no official difference between hills and mountains. The United Kingdom and the United States used to define hills as summits less than 1,000 feet. However, both countries abandoned the distinction in the mid-twentieth century.

    Sometimes, you'll find a hill made by people. This is called a mound. In the Midwest region of North America, a network of Native Americans known as the Hopewell created huge mounds. In fact, the Hopewell people are often called Mound Builders. The most well-known mounds are in Hopewell Culture National Historical Park, in the U.S. state of Ohio.

    The Hopewell people built mounds in the shape of spirals and domes. These mounds are about 9 meters (30 feet) tall and sometimes as wide as 305 meters (1,000 feet).

    Archaeologists are unsure what the mounds were used for. Some may have been burial mounds for important people, or they may have been used as astronomical observatories.

    Natural hills are formed all the time, by different types of geologic activity. One of these activities is faulting, which happens because the rocks underneath the Earth's surface are constantly moving and changing the landscape. Hills formed by faulting can eventually become mountains. The Himalayas in Asia, the tallest mountain range in the world, were once tiny hills. The Himalayas continue to grow because of faulting activity beneath the Earths surface.

    Hills are also formed because of erosion, which happens when bits of rock, soil, and sediment get washed away and placed in a pile somewhere else.

    Hills can be destroyed by erosion, as material is worn away by wind and water. Hills can also be created by erosion, as material from other areas is deposited near the hill, causing it to grow. A mountain may become a hill if it is worn down by erosion.

    Parts of the U.S. state of Indiana are almost entirely flat. However, other parts of the state have a ton of hills. Geologists and geographers have studied the lack of hills in northern Indiana. They discovered that during the Ice Age, glaciers covered the area, mowing down the landscape as they advanced like steamrollers. The glaciers started to melt once they reached the middle of the state. Running water from the melting glaciers helped form the hilly, rugged landscape of southern Indiana.

    There are a handful of different types of hills. A drumlin is a long hill formed by the movement of glaciers. A butte is a hill that usually stands alone in a flat area. It has steep sides and a flat top. The rest of the hill was eroded away. A tor is a rock formation on top of a hill.

    Sometimes, especially in the United Kingdom, a tor also refers to the hill itself. A puy is a cone-shaped, volcanic hill. A pingo is a mound of ice covered with earth. These are found in the Arctic and Antarctica.

    People have used hills for homes and urban areas for thousands of years. Many people have built their homes and villages on hills to avoid floods.

    The higher elevation also allows people to defend themselves. Ancient Rome, for example, was built on the city's seven hills so Romans could see their invaders coming from far away.

    The earth tones of Oregon's Painted Hills.

    City Upon a Hill
    The phrase city upon a hill is taken from the Bible, the holy book of the Christian religion. The phrase has come to be associated with the idealism of the United States. John Winthrop, a leader of the early European settlers of Massachusetts, hoped to establish a city upon a hill in Massachusetts in 1630. U.S. presidents from John Kennedy to Ronald Reagan also used the phrase when talking about the hope and promise of a democratic form of government.

    The Hill
    "The Hill" often refers to the activity of the United States Congress (the Senate and the House of Representatives.) Congress works on Capitol Hill.

    Hill of Ruins
    In ancient times, when one civilization conquered another the invaders would tear down an old city and just build their new city on top of the ruins. After hundreds of years of such processes, the result was a hill made of layer upon layer of old city debris. Thousands of these hills, called tels, can be found in the Middle East.

  • Term Part of Speech Definition Encyclopedic Entry
    ancient Rome Noun

    civilization founded on the Mediterranean Sea, lasting from the 8th century BCE to about 476 CE.

    archaeologist Noun

    person who studies artifacts and lifestyles of ancient cultures.

    Arctic Noun

    region at Earth's extreme north, encompassed by the Arctic Circle.

    Encyclopedic Entry: Arctic
    astronomical observatory Noun

    place for studying the stars and the universe beyond the Earth.

    Bible Noun

    holy book of the Christian religion.

    burial mound Noun

    area of raised earth above a grave or graves.

    butte Noun

    single hill or rock formation that rises sharply from a flat landscape, usually in a desert.

    Encyclopedic Entry: butte
    Congress Noun

    legislative branch of the government, responsible for making laws. The U.S. Congress has two bodies, the House of Representatives and the Senate.

    democracy Noun

    system of organization or government where the people decide policies or elect representatives to do so.

    destroy Verb

    to ruin or make useless.

    dome Noun

    shape that is half of a sphere.

    Encyclopedic Entry: dome
    drumlin Noun

    earthen mound shaped by glaciers.

    Earth Noun

    our planet, the third from the Sun. The Earth is the only place in the known universe that supports life.

    Encyclopedic Entry: Earth
    erosion Noun

    act in which earth is worn away, often by water, wind, or ice.

    Encyclopedic Entry: erosion
    faulting Noun

    movement of rocks and tectonic plates beneath the Earth's surface.

    flood Noun

    overflow of a body of water onto land.

    Encyclopedic Entry: flood
    geographer Noun

    person who studies places and the relationships between people and their environments.

    geologic Adjective

    having to do with the physical formations of the Earth.

    glacier Noun

    mass of ice that moves slowly over land.

    Encyclopedic Entry: glacier
    hill Noun

    land that rises above its surroundings and has a rounded summit, usually less than 300 meters (1,000 feet).

    Encyclopedic Entry: hill
    Himalaya Mountains Noun

    mountain range between India and Nepal.

    Hopewell Noun

    (500 BCE-200 CE) people and cultures of a trading network in the Mississippi and Ohio Valleys of North America.

    Ice Age Noun

    last glacial period, which peaked about 20,000 years ago.

    idealism Noun

    honoring or emphasizing the importance of noble ideas such as honesty or equality.

    invader Noun

    organism that enters an area to take control of it.

    John F. Kennedy Noun

    (1917-1963) 35th president of the United States.

    John Winthrop Noun

    (1588-1639) English settler and governor of the Massachusetts Bay Colony.

    landscape Noun

    the geographic features of a region.

    Encyclopedic Entry: landscape
    Midwest Noun

    area of the United States consisting of the following states: Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin.

    mound Noun

    hill built by people.

    mountain Noun

    landmass that forms as tectonic plates interact with each other.

    puy Noun

    small hill of volcanic origin.

    rock Noun

    natural substance composed of solid mineral matter.

    Ronald Reagan Noun

    (1911-2004) 40th president of the United States.

    sea level Noun

    base level for measuring elevations. Sea level is determined by measurements taken over a 19-year cycle.

    Encyclopedic Entry: sea level
    sediment Noun

    solid material transported and deposited by water, ice, and wind.

    Encyclopedic Entry: sediment
    soil Noun

    top layer of the Earth's surface where plants can grow.

    spiral Noun

    shape of a line curving around a single point.

    summit Noun

    highest point of a mountain.

    the Hill Noun

    Capitol Hill, the area of Washington, D.C., where the U.S. Congress works.

    tor Noun

    rock formation on top of a hill.

    urban area Noun

    developed, densely populated area where most inhabitants have nonagricultural jobs.

    Encyclopedic Entry: urban area
    USGS Noun

    (United States Geological Survey) primary source for science about the Earth, its natural and living resources, natural hazards, and the environment.

    Encyclopedic Entry: Surveying the United States
    village Noun

    small human settlement usually found in a rural setting.

    Encyclopedic Entry: village
    volcanic Adjective

    having to do with volcanoes.

    wind Noun

    movement of air (from a high pressure zone to a low pressure zone) caused by the uneven heating of the Earth by the sun.