Ushistory.org, The Philadelphia Campaign, 1777: From Rebels to Mature Army

http://www.ushistory.org/march/index.html

A privately managed site, this virtual guide offers one of the best web-based overviews of the Philadelphia Campaign. Written in an engaging style, the format also includes useful sidebars, driving directions and selected primary sources

Referenced in:
The Philadelphia Campaign
Dilworthtown
The Decisive Victory: Philadelphia and the Winning of the War for American Independence