The Great Chain could be dismantled and pulled ashore in winter, when the Hudson wasn’t navigable anyway, to protect it from being smashed apart by tide-tossed icebergs. Its placement in the river could also be adjusted using a pulley system. Just downriver, a second barrier of wooden booms was floated, making it nearly impossible for a ship to get up enough momentum to break through the chain – although the notorious traitor Benedict Arnold had advised the British that they could, when he handed over the plans to the fortification at West Point. They never tried.

The abandoned mansion is off the beaten path, seemingly stuck in a time when the Hudson Valley was a sleepy backwater. The Point, as it is known, is sequestered at the end of a winding road in a forested section of Mills-Norrie State Park, located in Staatsburg. It’s set at an angle on a high promontory of the Hudson River, which glimmers through the thick growth of trees. The windows are boarded up, the roof of the large stone portico at the entrance has half collapsed, the porch is gone and the bare lawn is surrounded by a utilitarian chain-link fence; yet the Gothic-style building, with its tall gables graced by carved verge boards, bay windows and squared-off, compact mass, exudes an echo of fairytale magic. Constructed of bluestone, whose soft, faded gray tones blend in with the site, the house has a cottagelike intimacy.