NEW YORK — It was wedged in a narrow, inaccessible space between two buildings, about three blocks from the World Trade Center site. And there it remained, hidden from view, for more than 11 years. Ground zero slowly gave way to a new tower. Protesters gathered nearby, angry over a planned Islamic center.

But this week, land surveyors happened upon it — a piece of a plane’s landing gear, apparently belonging to one of the two jets that slammed into the twin towers on Sept. 11, 2001, the police said.

On Wednesday, around 11 a.m., the surveyors called 911 to say they had found a piece of damaged machinery. What the police discovered was a component about 5 feet high, 3 feet wide and about 17 inches in depth. It was lodged in the narrow gap between 50 Murray St., a residential building, and 51 Park Place, which is empty. There, it had been “out of sight and out of mind for over a decade,” the Police Department’s chief spokesman, Paul Browne, said Friday.

That area is inaccessible from the street, Browne said, adding that a tiny door opens into the corridor from a neighboring building.

“The odds of it entering that space at exactly that angle that would permit it to squeeze in there,” he said, “it had to come in at almost precisely the right angle.”

Investigators are working under the assumption that the piece is “a portion of the landing gear of one of the two planes destroyed on 9/11,” Browne added.

He noted that the artifact bore a Boeing serial number and that personnel from the Police Department’s aviation unit had identified it as part of a landing gear. He also noted that it was found near where other wreckage from the jetliners was found shortly after the attacks.

Speaking later Friday, Police Commissioner Raymond Kelly did not completely rule out the possibility that the component had been lowered to the spot where it was discovered (some rope was entwined with it).

Park Place is about three blocks north of the World Trade Center site, and 51 Park Place is next to 45-47 Park Place and included in a plan by a developer to create a mosque and community center. The developer, Sharif El-Gamal, said in a statement that his company, Soho Properties, was cooperating with the authorities “to make sure this piece of evidence is removed with care as quickly and effectively as possible.”