American Archaeological Conservancy:
American Historical Association:
Archaeology Magazine (online):
Civil War in America:;; 
Discover Our Shared Heritage online travel itineraries/National Parks:
Ellis Island Museum:
Footnote (digital archive/historical documents partnership with National Archives) :
Gilder Lehrman Institute of American History:
Historical Markers Database:
Library of Congress:
Library of Congress - American Memory Project: 
Nanticoke-Lenni Lenape Indians:
National Archives & Records Administration:
National Daughters of the American Revolution site/library:
National Museum of American History:
National Parks Service (NPS) Guide:
 NPS/History and Cultural Resources:
National Register of Historic Places:
National Trust for Historic Preservation:
Organization of American Historians:
Philadelphia Historical Society/Research and Collections:
Powhatan-Renape Indians:
Preserve America:
Railroad Histories:;
Ramapough-Lenape Indians:
Timeline of the American Revolution:
Vintage Base Ball in America: