Wikipedia says:
Petersburg is an independent city in Virginia, United States located on the Appomattox River. The population was 33,740 at the 2000 census. It is in Tri-Cities area of the Richmond-Petersburg region and is a portion of the Richmond Metropolitan Statistical Area (MSA). The Bureau of Economic Analysis combines the city of Petersburg (along with Colonial Heights) with neighboring Dinwiddie County for statistical purposes. (...) more....
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