Among the natural wonders of the Hudson Highlands is a man-made curiosity that speaks of wealth and power from an earlier time. The Scottish-inspired castle on a small Hudson River island was never the mansion that some of us might assume as we flash by on the train. Instead, it’s the crumbling shell of a famous arsenal that once housed one of the most unique collections in the world.
The island arsenal was the creation of Francis Bannerman VI, a Scotland-born merchant who began his career in New York City as a munitions dealer at a young age. As a child he attended Navy auctions with his father, and learned the business of selling military castoffs. When the elder Bannerman left for the Civil War, Francis quit school and took on several jobs to support his family, including selling collected scrap.
Following the war, 14-year-old Bannerman set up shop first in Brooklyn and later Manhattan, continuing to purchase and resell government military surplus. He eventually needed nearly an acre of floor space to house his merchandise. The Francis Bannerman Sons store included Bannerman’s Military Museum, a vast collection of weaponry and war relics from around the world.
After acquiring loads of surplus live ammunition in 1898, including 30 million cartridges and barrels of black powder, Bannerman faced a dilemma. He required more storage space than his already overcrowded store could provide, and live ammo could not be stored within New York City limits. Then he heard of Pollepel, an uninhabited, rocky Hudson River island situated about 50 miles north of Manhattan. Given its location, the potential for moving goods upriver by barge and railroad, and the space to expand his growing empire, the nearly 7-acre island seemed the perfect solution.
Bannerman purchased Pollepel in 1900 from Mary G. Taft of Cornwall, and negotiated with the state for underwater rights surrounding the island. Inspired by structures he had seen on overseas buying trips — and no doubt by his background in Scotland, where real, centuries-old castles were commonplace — Bannerman sketched plans, and his vision of a protected yet highly visible arsenal began to come to life.
First, workers constructed a superintendent’s house and three-story storehouse on the island’s northern end, quickly followed by towers marking the boundaries of the island’s underwater rights and additional arsenals. Breakwaters and docks were created by sinking decommissioned barges and filling them with debris, while lumber from those same barges was used as flooring throughout the complex. Bannerman creatively incorporated military surplus, repurposing metal items into rebar and other supports, while cannons and cannonballs decorated the façade and grounds.
With the construction of a large castle-like tower, a moat, and drawbridge with a portcullis, the island complex was indeed a fortress. (A second smaller castle, “Crag Inch Lodge,” was built on a hill above the arsenal for use as a seasonal Bannerman family residence.) All the while, vast quantities of military stores were being transported to the new arsenal on the Hudson, including, as one newspaper noted, “enough powder to blast away the better part of Manhattan, enough heavy guns and ammunition to outfit a small army.”
Everything from suits of armor and ancient weaponry to musical instruments and sleeping bags made of reindeer skin were stored on the island and available for sale. The annual Bannerman Military Catalogue advertising the wide-ranging contents of “Our Island Arsenal,” became known as the best reference book on military apparatus.
The castle masonry featured the words “Bannerman’s Island Arsenal,” and the whitewashed walls of the No. 1 arsenal were used as a billboard to advertise both the Manhattan store address and the catalogue. These visuals allowed no doubt as to the ownership of the impressive site and the purpose of the business.
All construction ceased following Francis Bannerman’s death in 1918. In August of 1920, an accidental explosion of more than 200 pounds of shells and powder in the powder house caused extensive damage to the northwest portion of the castle. Sections of the wall were blown into and across the river, while effects of the explosion could be felt as far away as Poughkeepsie and Peekskill. From then on, the Bannerman family almost completely stopped using the island residence.
Though the business remained housed on the island over the ensuing decades, the castle began to deteriorate. Remaining ammunition and weapons were removed, and it was closed for good by 1959. A fire gutted the complex on August 8, 1969, shortly after the property had been acquired by the Taconic State Park Commission. More collapses in later years further damaged the distinctive Hudson River landmark.
Since 1993, the not-for-profit Bannerman Castle Trust, in conjunction with the New York State Office of Parks, Recreation and Historic Preservation, has been dedicated to preserving the history of the island, raising funds to stabilize the castle and providing public access to the site. Sections of the castle are now supported by steel braces, with the hope that the foundation can be stabilized and portions of the complex eventually rebuilt.
Although Francis Bannerman’s time on the island was short-lived, more than a century later his presence in the region endures. Today, through the efforts of the Bannerman Castle Trust, the island has become an interactive museum where visitors can view his original sketches and a small selection of items from his collection, explore the Bannerman residence and walk the garden trails overlooking the remains of his once majestic Bannerman Island Arsenal.
