“Because of its prominent massing, design and height, the building will be read as a visually distinctive addition to Park Avenue, rather than as a midblock building,” wrote the Zeckendorfs, whose portfolio includes 15 Central Park West, and who, along with the administrator of Christ Church, declined to be interviewed for this article. “Assigning the street address to the building therefore would not create confusion as to the building’s location given its prominent visibility on Park Avenue.”

For those in need of additional guidance, there will also be “a robust cantilevered canopy that will act as a beacon off Park Avenue,” the Zeckendorfs wrote, to say nothing of “an architecturally distinctive sidewalk incorporating a transition in color and texture from the existing concrete sidewalk along Park Avenue. This change in appearance will lead visitors to the new building from Park Avenue and provide yet another visual connection.”

In other words, follow the yellow brick road — because there won’t be an entrance to 520 Park Avenue on Park, since the building has no frontage on Park.

The Zeckendorfs wanted that 520 so badly that, in addition to the $30.383 million they paid for the air rights, they wrote Mr. Stringer that in return for “an irrevocable license to use its Park Avenue address,” Zeckendorf Development would “ensure vital ongoing financial support for the church.”

Image The new address for Christ Church is 524 Park Avenue. Credit... Pablo Enriquez for The New York Times

But 520 Park Avenue is not the only building to cause head-scratching and GPS-gazing. The principal entrance to the soon-to-be-completed high-rise 432 Park Avenue is on East 56th Street, although the site does have 75 feet of frontage on Park Avenue. “They wanted to create a private and dramatic porte-cochère for residents and their vehicles, which wasn’t possible on Park Avenue from a design point of view,” said Richard Wallgren, the director of sales for the building, developed by CIM Group and Macklowe Properties.

Meanwhile, 1049 Fifth Avenue, a prewar condominium, is halfway down East 86th Street with no frontage on Fifth Avenue at all. And many corner properties have their canopies on cross streets but hold tight to their Fifth or Park Avenue identities, among them 1140, 1148 and 1150 Fifth Avenue. A few buildings, sensing the confusion their address engenders, toss a lifeline: The side-street canopy for 1060 Fifth Avenue also reads 1 E. 87th St.