The Hudson River's 'Oddest Attraction' Is A Supposedly Haunted Rocky Island With Castle Ruins

The Hudson River flows through New York and a few other surrounding states and has long been a travel destination that blends natural beauty with deep historical roots. Towering cliffs, scenic trails, and charming towns line its shores, offering a retreat from the chaos of city life. But beyond its picturesque landscapes, the Hudson is also home to stranger, more mysterious attractions. One such curiosity is Esopus Island, a scenic camp area with a mysterious past. But for the most striking sight along the river, look no further than a rocky, castle-crowned island sitting in the Hudson Highlands. A castle in the United States is unusual enough — Castle Otttis, an iconic landmark in St. Augustine, Florida, is a rare example, but most Americans would expect to see medieval-style fortresses in Europe. Yet, one stands right in the middle of the Hudson River.

That would be Bannerman Castle on Pollepel Island, dubbed "the Hudson River's oddest attraction" by MTA Away. Its Scottish-inspired silhouette rises dramatically from the water, a ghostly ruin framed by lush greenery and jagged cliffs. Built by arms dealer Francis Bannerman VI in the early 1900s, the castle wasn't a fairytale residence but an elaborate arsenal designed to house his surplus of military equipment. Complete with towers, a storehouse, and a manmade bay, Bannerman Castle remains one of the Hudson Valley's most enigmatic landmarks.

Pollepel Island sits in the Hudson Highlands, where the river narrows and the mountains loom on either side. Long before Bannerman's arrival, the island carried a more sinister reputation. Native American tribes believed it to be haunted by dark spirits, a superstition that Dutch sailors later adopted. According to one legend, these sailors had an unusual initiation ritual: Abandoning first-timers on the island to appease a fabled goblin king, only retrieving them on the return journey. Later, during the Revolutionary War, the American army attempted to block British ships from advancing upriver by constructing chevaux de frises — underwater spiked barriers — around the island.

Francis Bannerman VI purchased the island in 1900, transforming it into his personal fortress. Born in Scotland and raised in Brooklyn, Bannerman was a munitions dealer who needed a remote location to store his surplus of ammunition. Rather than build a simple warehouse, he chose to construct a castle inspired by the fortresses of his homeland. The complex featured a storehouse, towers, and breakwaters. Adding to its character, the castle has no right angles and some of its walls were reinforced with bed frames salvaged from military surplus.

Bannerman Castle was abandoned by the Bannerman family in the 1950s, and time has not been kind to the structure. A fire in 1967 reduced most of the interior to rubble, leaving only the outer walls standing. Further collapses, including a partial wall collapse in 2009, have added to its eerie appearance. Today, the island is owned by New York State and managed by the Bannerman Castle Trust, which has worked to restore the gardens and terraces. While random explorations are off-limits, visitors can still get a closer look through guided tours or boat trips along the Hudson.

For those eager to step onto Pollepel Island, several guided tours and events are available throughout the year. The Bannerman Castle Trust offers a boat and walking tour for $45, which includes a 30-minute scenic boat ride from Beacon, New York, followed by a 45-minute guided exploration of the island. You can get to Beacon from New York City's Grand Central Terminal by an hour-and-a-half train ride on the Metro-North Railroad. An alternative is the self-guided tour, which also costs $45 and allows visitors to roam the ruins at their own pace while enjoying live music. For something a little more unique, the island hosts seasonal events such as a monarch butterfly tour, Hudson Valley Shakespeare Festival productions, and even movie nights at the castle. All tickets must be booked through the Bannerman Castle website in advance.

Beyond the castle, the surrounding Hudson Valley offers plenty to explore. Breakneck Ridge provides a thrilling hike, with breathtaking views of the river and valley. The nearby towns of Cold Spring and Beacon boast cozy cafes, antique shops, and art galleries. You can also admire the castle from afar and see New York's stunning fall foliage on a Hudson River cruise. For an abandoned fortress once filled with explosives and rumors of ghosts, Bannerman Castle has a surprising ability to enchant those who visit.