If the newest, last stretch of the High Line doesn’t make you fall in love with New York all over again, I really don’t know what to say. Phase 3 of the elevated park, which opens on Sunday, is a heartbreaker, swinging west on 30th Street from 10th Avenue toward the Hudson River, straight into drop-dead sunset views. It spills into a feral grove of big-tooth aspen trees on 34th Street.

It’s hard to believe now that some New Yorkers once thought renovating the decrepit elevated rail line was a lousy idea. Not since Central Park opened in 1857 has a park reshaped New Yorkers’ thinking about public space and the city more profoundly. Like Frank Gehry’s Guggenheim museum in Spain, it has spread a dream, albeit largely a pipe dream, around the world: how one exceptional design — in this case, a work of landscape architecture — might miraculously alter a whole neighborhood, even a whole city’s fortunes.

Image Urban choreography: A westward view from the third and final leg of the High Line, which opens to the public Sunday. Credit Todd Heisler/The New York Times

Yes, at roughly $35 million, Phase 3, like the rest of the High Line, cost more per acre than probably any park in human history. With most city parks struggling to make ends meet, that kind of money is an inevitable source of resentment, notwithstanding that the High Line was, in significant measure, constructed and is almost exclusively maintained with private funds.

And, yes, nowhere is the city’s widening economic divide clearer to see than along this stretch of Manhattan’s West Side. The new phase loops around Hudson Yards, a 26-acre site becoming a multibillion-dollar architectural petting zoo, with super-tall office and apartment towers, at least one of them to rise higher than the Empire State Building.