参考资料：
1.https://en.wikipedia.org/wiki/History_of_Philadelphia
2.https://en.wikipedia.org/wiki/List_of_capitals_in_the_United_States
3.https://en.wikipedia.org/wiki/Washington,_D.C.
4.https://en.wikipedia.org/wiki/William_Penn
5.https://en.wikipedia.org/wiki/Pennsylvania_Mutiny_of_1783
6.https://en.wikipedia.org/wiki/Compromise_of_1790
7.https://en.wikipedia.org/wiki/Columbia_(personification)
*本文内容为作者提供，不代表地球知识局立场
封面：壹图网
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