The well - known Rushmore National Monument in the United States is built on the Rush More Peak, 1829 meters above sea level, of the Black Hills in the southwest of South Dakota. It is a group of huge stone statues of four American presidents, George Washington, Thomas Jefferson,Abraham Lincoln and Theodore Roosevelt. President Washington is the founding father of the country;the 3rd President Jefferson drafted the U. S. Declaration of Independence;the 16th President Lincoln issued the Emancipation Proclamation and the26th President Roosevelt protected the average people's right to compete fairly with trusts. All of them,made outstanding achievements for their country. They were pioneers of U. S. history. The stone statues of presidents were built at the suggestion of an historian in the State of Dakota,with a view to carrying forward the U. S. pioneering spirit everlastingly. The statues are 18 meters high. They are the highest and greatest realistic stone statues in the world,taller than a 6-storied building and larger than the Great Sphinx of Egypt. The size of each head is 20sq mt,with a 20-meter- long face,a 7-meter -long nose,a 2.6-meter- wide mouth and two 1.5-meter -wide eyes. Though not facing the same direction,they are all lifelike and look ahead gravely in harmony with fixed gazes. On clear days,one can have a sight of the four presidents with their firm and steady expression at a distance of dozens of kilometers. Since the stone sculpture is unique in style,the Monument is now the U. S. National Art Centre of Popular Education. Groups of people keep streaming everyday to the site for a visit and tourists across the world are also interested in taking a view of this great Monument. Why were those four presidents chosen ?Because the four presidents  _  .
were pioneers of US history made great contributions to their country played an important role in American history all of the above