There’s a wonderful term for the dirt trails that people leave behind in parks: desire lines.

Cities also have desire lines, marked by economic development and evolving patterns of travel. In New York, Manhattan was once the destination for nearly all such paths, expressed by subway tracks that linked Midtown with what Manhattanites liked to call the outer boroughs.

But there is a new desire line, which avoids Manhattan altogether.

It hugs the waterfronts of Brooklyn and Queens, stretching from Sunset Park past the piers of Red Hook, to the Brooklyn Navy Yard, through Greenpoint and across Newtown Creek, which separates the two boroughs, running all the way up to the Triborough Bridge in Astoria.

The desire line is now poorly served by public transit, even as millennials are colonizing Astoria, working in Red Hook, then going out in Williamsburg and Bushwick — or working at the Navy Yard, visiting friends in Long Island City and sleeping in Bedford-Stuyvesant.

They have helped drive housing developments approved or built along the Brooklyn waterfront, like the one by Two Trees at the former Domino Sugar Refinery. But this corridor isn’t only for millennials. It’s also home to thousands of less affluent New Yorkers struggling to get to jobs and join the work force.