1800 |
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The new city of Washington, D.C. becomes the United States capital. |
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Free African Americans in Philadelphia unsuccessfully petition the United States Congress to end enslavement. |
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A Philadelphia shoemaker is the first to design shoes especially for the right and left feet. |
1801 | 
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Mastodon fossils are discovered on a New York farm, the first skeletons ever found of the extinct mammal. |
1802 |
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Gideon Putnam builds a resort hotel, one of the earliest in America, at Saratoga Springs, New York. |
1803 |
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The United States more than doubles its size after buying over 820,000 square miles of land, known as the Louisiana Purchase, from the French government. |
1804 |
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Merriwether Lewis and William Clark begin their exploration of the vast Northwest territory, traveling from the Mississippi River to the Pacific Ocean. |
1805 |
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A covered bridge, America's first, is built over the Schuylkill River near Philadelphia. |
1806 |
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Zebulon Pike explores the territory that later became the American southwest, discovering Pike's Peak, the famous Colorado mountain named for him. |
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Congress authorizes improvements to the Natchez Trace, a Native American trail running from Nashville, Tennessee to Natchez, Mississippi, turning it into a road for American settlers.
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1807 |
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Robert Fulton's steamboat, the Clermont, makes its first run from New York City to Albany in 32 hours, traveling at the top speed of 5 mph. |
1808 |
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The United States prohibits the importation of Africans for enslavement. |
1809 |
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William Maclure publishes the first detailed geological survey of the United States. |