Before this section of the High Line opened, the couple, who have lived here for eight years, followed the advice of an architect and installed glass brick in the windows, which were once loading bays for the former factory building. “It was the perfect solution,” Mr. Saternow said, explaining that the glass is soundproof and lets in light but not prying eyes.

In other parts of the apartment, the couple has played up their vantage on the High Line, especially in Mr. Harwood’s north-facing office. His desk is perched right over the park, and on some evenings, parkgoers can watch him typing. “We designed it that way,” Mr. Saternow said. “We knew it would be the best view in the house.”

But the glare from the sun creates a natural blind during the day. In fact, standing in Mr. Harwood’s office and looking out at the people on the High Line, one has the odd sensation of invading their privacy. They take pictures or lie on the grass, unaware that someone is watching from behind the sun-darkened window.

Mr. Saternow said he has developed a casual, if somewhat contradictory, approach that one hopes those on the High Line also follow: “You sort of look and don’t look.”

245 TENTH: HOW LOW CAN YOU GO?

Benjamin and Michele Yogel don’t have the bedroom with the best view in their fifth-floor west-facing apartment. That distinction belongs to their 2-year-old daughter, Penelope, who enjoys a Technicolor shot down the High Line from her corner room.

“My daughter looks out the window and waves to everyone,” said Mr. Yogel, 34, a private equity manager who moved here in March with his family not because of the High Line, but because of the proximity to Avenues: The World School, a private school in Chelsea that his 4-year-old son, Oliver, attends.

Still, the Yogels, who once lived in an apartment facing a brick wall, realize that their new home is special. “The people who walk by think this is the most amazing place to live,” said Ms. Yogel, 33.