Fort Mercer

Fort Mercer was a fort on the Delaware River in New Jersey constructed by the Continental Army during the American Revolutionary War. Built by Polish engineer Thaddeus Kosciuszko under the command of George Washington, Fort Mercer was built in 1777 to block the approach to Philadelphia, Pennsylvania in concert with Fort Mifflin on the Pennsylvania side. Fort Mercer was located in an area called Red Bank, in what is now the borough of National Park, Gloucester County, New Jersey. The fort was named in honor of Brigadier General Hugh Mercer who had died earlier that year at the Battle of Princeton. The fort's site is now part of Red Bank Battlefield Historical Park, which includes a monument and museum. Several cannons attributed to British warships lost supporting the attack on the fort, and others found buried at the fort itself, are in the park.
Fort Mercer was built and Fort Mifflin rebuilt and garrisoned to protect a line of chevaux de frise obstacles across the Delaware River. Fort Billingsport was built downriver to protect another line of these obstacles. Fort Mercer had earthen walls with a surrounding ditch, topped with a log palisade. The fort was about 320 yards long and 50 yards wide and mounted 14 cannons, with bastions on the landward corners. A separate outer redoubt was located north of the fort, but this was not garrisoned. The fort could accommodate a garrison of 1,500 men, but only 600 were available, mostly Rhode Island troops of the Continental Army commanded by Colonel Christopher Greene, also a Rhode Islander. French officer Thomas Duplessis made the fort more defensible by the small garrison by having a wall built inside the river side of the fort.

Wikipedia