The stakes were high in fall 1777 as the British Navy sailed up the Delaware River toward Philadelphia.
Gen. George Washington told the American defenders of Fort Mifflin, just south of the city, to hold on "to the last extremity" while he moved his tattered army to Valley Forge. They did -- for six weeks, under the greatest naval bombardment of the Revolutionary War.
Some of the thousands of artillery projectiles that rained down on them are exhibited at the new Museum of the American Revolution, along with other rare artifacts, documents, and paintings connected to historic sites nearby in Pennsylvania and New Jersey.
Given the proximity of all these places where the American Revolution unfolded, the museum sees itself as "a visitor center for the American Revolution, a great starting point," said museum vice president R. Scott Stephenson. "You can move out from here like the layers of an onion, moving farther and farther afield."
Fort Mifflin is one of six sites in and around Philadelphia that belong on the must-see list for visitors looking to explore the story of the Revolution beyond the museum walls. Here is our select guide to peeling the onion:
Two blocks away: Independence Hall
Just a brief walk west on Chestnut Street, between Fifth and Sixth Streets, is the nation's birthplace -- Independence Hall -- where the Continental Congress met, where Washington was appointed commander-in-chief, and where independence was proclaimed by representatives of the 13 colonies.
Part of the site has been recreated by the new museum in a so-called pocket theater, where visitors view a five-minute film while sitting in Windsor chairs like those the founders used. Detailed woodwork mimics the room where independence was debated. But there's no substitute for the real thing.
It was from the cupola at Independence Hall that a bell sounded in 1776 to mark the reading of the Declaration of Independence. Later known as the Liberty Bell, it's housed just across the street.
Independence Hall is open 9 a.m. to 5 p.m. daily. Admission: Walk-up tickets on the day of a visit are free, and reserved tickets cost $1.50 each. Timed-entry tickets are required March-December. Information: 215-965-2305 or www.nps.gov/inde.
Just down I-95: Fort Mifflin
The Americans who held out at Fort Mifflin for a month and a half in 1777 against the overwhelming firepower of the British navy eventually retreated across the Delaware River to Fort Mercer in New Jersey. But Fort Mifflin's role in American history continued, into the War of 1812 and beyond. During the Civil War, it housed Confederate prisoners of war.
The fort is off the beaten path for tourists, on a marshy site next to Philadelphia International Airport, where it's under the flight path of descending aircraft. Visitors can climb battery emplacements to take in the view and imagine the British navy approaching up the Delaware. They're generally free to wander the fort's parade grounds, magazines, and other historic buildings.
Fort Mifflin, at 82 Fort Mifflin Rd., is open from 10 a.m. to 4 p.m., Wednesday through Sunday from March 1 to Dec. 15 and other times by appointment. Admission: $8 for adults; $6 for seniors; $4 for children and veterans, and free for children age 5 and under. Information: 215-685-4167 or www.fortmifflin.us/contact-us/.
In the scenic Brandywine Valley: Brandywine Battlefield
In the Revolution's longest (11-hour) single-day battle, the British and American armies clashed across the landscape near Chadds Ford at the Brandywine Battlefield on Sept. 11, 1777. The site is now a National Historical Landmark in Chester and Delaware Counties, roughly 45 minutes southwest of the new museum.
A rare wooden canteen belonging to an American soldier who fought at Brandywine is on display at the Museum of the American Revolution. It's marked "USTATES," indicating Continental Army use. The museum also displays a detailed plan/map by British engineers showing British, Hessian, and American troop positions and movements during the Battle of Brandywine.
Brandywine Battlefield Park is the central site for tourists who'd like to visit the sprawling battlefield area. Two historic houses offer tours (Washington used one of them, the Benjamin Ring House, as his headquarters), and there's a visitor center with a small museum and gift shop.
Visitors who call ahead can also hire a guide to take them around the battlefield's many other sites. An encampment day is scheduled for May 13; a two-day Battle of Brandywine reenactment takes place Sept. 16-17.
The visitor center at 1491 Baltimore Pike in Chadds Ford is open from 9 a.m. to 4 p.m. Thursday through Saturday and from noon to 4 p.m. on Sunday. Admission: $11 to tour both houses, $5 for the museum only, including an orientation film. Information: 610-459-3342 or www.brandywinebattlefield.org.
In Philadelphia's historic Germantown neighborhood: Cliveden Mansion
Once Washington regrouped after Brandywine, he struck the British on Oct. 4, 1777, at Germantown. The enemy initially fell back, except for about 100 redcoats who held Cliveden Mansion. When British reinforcements arrived across a wider front, Washington was forced to withdraw.
Among the items exhibited at the Museum of the American Revolution is a pair of English holster pistols that belonged to German American Brig. Gen. John Peter Gabriel Muhlenberg, who carried them at the Battle of Germantown. The museum also displays a 1782 painting of the battle by Italian artist Xavier della Gatta.
Tours of historic Cliveden, with its period furniture and musket-ball-pocked walls, are given on the hour from noon to 3 p.m. Thursday through Sunday April through December. Reenactors recreate the Battle of Germantown annually on the first Saturday of October.
The house and its visitor center are on the 6400 block of Germantown Avenue. Admission: $10 for adults, $8 for students. Information: 215-848-1777 or www.cliveden.org.
In the western suburbs: Valley Forge National Historical Park
Washington's army suffered through a difficult encampment at Valley Forge from December 1777 to June 1778. The march to Valley Forge was commemorated in a renowned and often-reproduced 1883 painting by William Trego, now on display at the Museum of the American Revolution.
The new museum also exhibits shovels used by soldiers, a toothbrush, buttons and buckles from uniforms, a leather packing case belonging to Washington, and a set of silver camp cups for wine.
The site of the encampment is now designated the Valley Forge National Historical Park, a 50-minute drive from Philadelphia. Visitors can tour recreated log cabins where survivors from Peter Muhlenberg's brigade encamped, view statues and historic monuments, and visit historic structures, including the restored Colonial house Washington used as a headquarters.
Visitor center at 1400 N. Outer Line Dr. in King of Prussia, open 9 a.m. to 5 p.m. daily. Information: 610-783-1000 or www.nps.gov/vafo.
In Bucks County, Washington Crossing Historic Park
Another local historic attraction is Washington Crossing Historic Park, at the site where Washington and his army crossed the Delaware River on Dec. 25, 1776, to make a surprise attack on the Hessian soldiers at Trenton on the morning of the 26th.
The crucial days from the Battle of Trenton to the Battle of Princeton, which followed, can be traced at the Museum of the American Revolution on an interactive map animated by LED lights that shows troop movements. The museum also displays the sword that American Gen. Hugh Mercer used before he was mortally wounded at Princeton, and some items from Hessian soldiers.
A new visitor center at the Bucks County park orients guests to the historic grounds, where costumed reenactors show off recreations of the Durham boats that ferried Washington and his troops across the Delaware and talk about the battles at Trenton and Princeton. The park also hosts an annual Christmas Day reenactment of Washington's crossing.
The visitor center is at 1112 River Rd., Washington Crossing. It's open 10 a.m. to 5 p.m. daily. Admission: Grounds and visitor center, free; guided tours $6 (last tour 4 p.m.). Information: 215-493-4076 or washingtoncrossingpark.org. Just across the river, New Jersey's Washington Crossing State Park also has a visitor center, at 355 Washington Crossing-Pennington Rd. in Titusville.