The site on the Schuylkill River in Pennsylvania, about 32 km (20 miles) to the north-west of Philadelphia, where George Washington's Continental Army spent the winter of 1777–8 in conditions of extreme hardship.
Definition of Valley Forge in US English:
Valley Forge
proper nounvæliˈfɔːdʒ
The site on the Schuylkill River in Pennsylvania, about 20 miles (32 km) northwest of Philadelphia, where George Washington's Continental Army spent the winter of 1777–78 in conditions of extreme hardship during the American Revolution.