Fort Delaware, situated on Pea Patch Island in the Delaware River, was a harbor defense facility built to protect the ports of Wilmington, Delaware, and Philadelphia, Pennsylvania. The post is well known for its use as a prison camp during the Civil War, housing more than 12,000 Confederate prisoners. The prisoner of war camp’s unsanitary conditions, partly stemming from poor drainage, gave the fort the reputation of being the Union’s counterpart to the infamous Confederate prisoner of war camp at Andersonville, Georgia.
The State of Delaware deeded Pea Patch Island to the U.S. government in 1813 to build a fort to protect the entrance to the Delaware River. The first earthwork fortification was constructed the same year and served until 1821, when it was dismantled.
A second masonry “star fort” was built of brownstone with a wooden interior starting in 1819. The star fort was designed by army engineer Joseph G. Totten and construction was supervised by Captain Samuel Babcock. Babcock supervised the work until 1824, when construction was delayed due to uneven settling, improper pile placement, and the island’s marshy nature. Babcock was severely criticized for altering Totten’s original plans without orders and was required to appear before a court-martial in late 1824. In the end, the court determined he was not guilty of neglect but rather an error in judgment, and he was acquitted. Major Alexander C.W. Fanning took command, and the 2nd U.S. Artillery soldiers manned the post.
On February 8-9, 1831, a fire erupted at the fort, destroying most buildings. What was left of the post was torn down in 1833 to make room for a new fortification. The stone was used to reinforce the sea wall.
In 1847 Congress appropriated one million dollars to construct a Third System masonry fort on Pea Patch Island. Captain Richard Delafield of the Corps of Engineers designed the new fort, and work on the bastioned pentagon-shaped fort began in 1848. The cost of driving the pilings comprised the million-dollar appropriation, and Congress provided another million to continue the work. It was 1849 before actual construction on the fort, which was to surpass Fort Sumter, South Carolina, in size, began, and it was not completed until 1859.
The fort covered about six acres and initially had a parade ground that covered more than two acres. Its 32-foot high walls were constructed of solid granite blocks and bricks, varying in thickness from seven feet to 30 feet, and were surrounded by a 30-foot-wide moat, crossed by a drawbridge on the Delaware side leading to the fort’s sally port, or principal entrance. At this time, the post was the largest masonry fortification in the United States. More than 25 million bricks are said to have been used for the fort and barracks.
By the mid-1850s, several additional buildings — mostly workshops and living quarters — were ranged along the interior face of the sea wall in the southeastern and northern sectors of the island. The fort was complete by 1859, its rehabilitation costing more than $1,305,000. As a result of all this construction activity, the area surrounding the main fort, filled with shops, warehousing, sheds, houses, shanties, and other structures, evolved into a well-established civilian settlement. Services such as a bakery, laundry, and even a school were included within this community.
Fort Delaware’s greatest period of activity occurred during the Civil War. A single company of regular artillery occupied the fort in February 1861. The Commonwealth Artillery of Pennsylvania was the first volunteer unit to move in after the war began. Following the Battle of Kernstown, Virginia, in 1862, 250 of Stonewall Jackson’s army troops were brought to the island as the first Confederate prisoners of war, even though the fort had not been planned for such use up to that time. That year, wooden barracks were erected to house 2,000 prisoners, but they were quickly overcrowded.
Most of the Confederates captured at Gettysburg, Pennsylvania, in July 1863 were also imprisoned at Fort Delaware. Initially, the prisoners were housed in brick barracks within the main fort. By that time, there were some 8000 prisoners on the island, and the barracks were expanded to house 10,000. There were some 12,500 prisoners on the island in August 1863.
As the prisoner population grew, the prison quarters were relocated to the northwestern half of the island. Prisoners were housed in crudely constructed, fence-enclosed barracks in an eight-acre compound. Each camp was arranged into ten rows of barracks. Each barrack was subdivided into chambers, which were known as “divisions.” A division was 19 by 60 feet with a narrow passage separating bunks in three tiers on either side and housed from 400 to 900 men. One Confederate prisoner described the camp:
“The pens were formed by enclosing a parallelogram of some eight acres by a continuous line of rude one-story pine barracks running around the four sides. The enclosure, or courtyard, was divided into two yards by a double line of high plank fence, with a parapet on the top, for sentries to walk and overlook the prisoners in each square.
An alley ten feet broad separated the two fences, preventing intercourse between the two pens and giving access to gates opening into each. Officers occupied the smaller pen nearest the fort; privates the other, which, though larger, was many times more crowded.
The row of barracks were under a continuous roof but were divided into rooms called “Divisions” numbered from no. one to forty. The buildings were really shells, constructed of long planks standing on end, in line, like a double fence, or covered bridge, running around three sides of a square. The floor was as rough as a stable; the roof leaky as a sieve; the weatherboarding so open that you could thrust your hand between most of the planks, and great drifts of snow accumulated upon our beds every night in winter”
Hospital facilities and other structures, including a kitchen and bakery, sutler’s shops, latrines, surgeon’s quarters, garrison barracks, an “oyster house,” beer saloon, tailor shop, officer’s gymnasium, commissary, and storehouse and watch houses, were also constructed, sufficient eventually to support a prison population of up to 13,000 with their attendant guards and service staff. The prisoners themselves erected other temporary structures to suit their needs. These included barber shops, a ring maker’s tent, and arbors for shade. The prisoners also erected a chapel used by the Federal officers and their families. During this period, virtually the entire island was improved in some form or other to accommodate the vastly increased population. Most of the new construction took place in the northwest half of the island, but the older developed southeast end continued in use and saw the erection of some additional buildings.
During the war, about 2,900 prisoners died while incarcerated at Fort Delaware, of which about 2,400 were buried in a national cemetery at Finn’s Point, New Jersey, just across the Delaware River. Despite a large number of deaths, the prison at Fort Delaware had one of the lowest death percentages (10%) of any U.S. Civil War prison. Half of the deaths occurred during a smallpox epidemic in 1863. Other deaths occurred due to cholera, pneumonia, scurvy, typhoid, and other illnesses. During this time, 109 Union soldiers and about 40 civilians on the island also died.
Among the political prisoners housed at the fort were Burton H. Harrison, private secretary to Jefferson Davis, and Governor F.R. Lubbock of Texas, who was the last prisoner at the fort in 1865.
After the Civil War, the resident population of Pea Patch Island declined dramatically, and the focus shifted from housing prisoners to improve the fort’s defensive systems. In the early 1870s, the barbette platforms located in the bastions of the main fort were modified to accommodate 15-inch Rodman guns. Concrete and earth-covered service magazines were also added. In 1894 a massive two-story concrete emplacement for three 12-inch guns on disappearing carriages was constructed, covering more than half of the parade ground. Outside the main fort, two rapid-fire gun batteries and a torpedo casemate were constructed. Still, the majority of the earlier civilian and prison-related structures were either taken down or fell into disrepair. By the final decade of the 19th century, no more than a dozen or so frame buildings were surviving from the earlier period. More artillery improvements were made in the 1890s for the Spanish-American War when the fort was again fully garrisoned.
In 1903, practically all of the garrison was removed except for a token force. The last significant alterations to the island occurred in 1904-08 when between 3 and 12 feet of earth was spread over the island’s surface, raising its overall elevation considerably. In preparation for this work, nearly all the other remaining buildings on the island were raised. Except for two buildings saved as quarters for white and black laborers, only the fort, the new gun emplacements, the torpedo casemate, and a coal bin were allowed to remain.
From 1908 to 1945, Fort Delaware functioned in a secondary defensive role to the nearby Fort Dupont and Fort Mott, respectively, on the Delaware and New Jersey sides of the river. Throughout this period, for the most part, the fort was occupied only by a small caretaker garrison. During World War I, Fort Delaware was manned by the 3rd Company Coast Artillery for a brief period. With the beginning of World War II, new plans for the defense of the Delaware River were developed. Rather than focusing on the point where the river expanded into the bay as the Fort Delaware-Fort Mott-Fort Dupont line of defense had these plans called for the fortification of the mouth of the bay. The Fort Delaware garrison was increased in size until these new defenses were completed. Once finished, the large gun emplacements and sighting towers at Cape May Point, New Jersey, and Fort Miles, Cape Henlopen, Delaware, rendered Fort Delaware obsolete.
In 1943 the big disappearing guns were removed for scrap iron. In October 1944, the War Department declared the site surplus. The island reverted to the State of Delaware, with the Philadelphia District of the U.S. Army Corps of Engineers retaining 19 acres for river and harbor maintenance projects.
In 1951 the island became a Delaware State Park, and work began to preserve the remaining buildings and open them to the public. Today the site interprets its history for visitors with tours, demonstrations, and events. Costumed interpreters provide information and tours of the parade ground, officers’ quarters, barracks, kitchen, blacksmith shop, ordnance room, and more. Fort Delaware is also known for its “ghostly” activity, and paranormal tours are offered in the fall.
Located in the Delaware River, just one mile from Delaware City, access to Pea Patch Island and Fort Delaware is by ferry only. The ticket office and ferry dock are located at 45 Clinton Street in Delaware City.
Fort Delaware State Park Office
Grass Dale Center
108 N. Reedy Point Road
Delaware City, DE
“Things here are not quite as bad as I expected to find them. They are, however, bad, hopeless, and gloomy enough without any exaggeration. We went into dinner about three o’clock, which consisted of three hardtack, a small piece of meat (about three bites), and a pint tin cup of bean soup. We only get two light meals a day.”
— Confederate Private Henry Berkeley.
Compiled and edited by Kathy Alexander/Legends of America, updated January 2023.
Forts & Presidios Across America
Fort Delaware – National Register Nomination
Fort Delaware State Park
Historic American Engineering Record