<Li> Quinton's Bridge </Li> <Li> Carlisle Peace Commission </Li> <P> Valley Forge functioned as the third of eight military encampments for the Continental Army's main body, commanded by General George Washington . In September 1777, British forces had captured the American capital of Philadelphia . After failing to retake the city, Washington led his 12,000 - person army into winter quarters at Valley Forge, located approximately 18 miles (29 km) northwest of Philadelphia . They remained there for six months, from December 19, 1777 to June 19, 1778 . At Valley Forge, the Continentals struggled to manage a disastrous supply crisis while retraining and reorganizing their units . About 1,700 to 2,000 soldiers died due to disease, possibly exacerbated by malnutrition . </P> <P> Today, Valley Forge National Historical Park preserves and protects over 3,500 acres of the original encampment site . </P>

When did the continental army leave valley forge