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Why is Pennsylvania called the Keystone State?
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Independence Hall, a historic red brick building with a central clock tower and steeple, stands in front of trees and an American flag at sunset in Philadelphia, Pennsylvania.
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Independence Hall, a historic red brick building with a central clock tower and steeple, stands in front of trees and an American flag at sunset in Philadelphia, Pennsylvania.
Independence Hall Independence National Historical Park in Philadelphia.

Why is Pennsylvania called the Keystone State?

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Pennsylvania is called the Keystone State because of its central location among the original 13 American colonies and its crucial role in the founding and development of the United States. The term keystone refers to the stone in an arch that is located in the middle of the structure and is essential in maintaining its stability. Pennsylvania played a similarly integral role in the nation’s formation.

Pennsylvania was a hub of economic and political activity beginning in the colonial period, and Philadelphia, the state’s largest city, was vitally important in the Revolutionary era. It hosted the First and Second Continental Congresses and was where the Declaration of Independence was signed. It also served as the young country’s capital from 1790 to 1800. Philadelphia also was the United States’ center of publishing, foreign commerce, and finance for many years.

Pennsylvania’s contributions were not limited to politics. The state was a leader in industrial development, contributing significant advancements in coal mining, oil drilling, and steel production.

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