The Bronx lies closer to Randalls Island than any other borough does, separated by less than 50 feet in some places across a narrow waterway known as the Bronx Kill.

But many Bronx residents find it so difficult to reach the island’s expanse of playing fields, bike trails and nature areas that they simply do not bother to go. The only direct route by foot is across a busy expanse of the Robert F. Kennedy Bridge (formerly called the Triborough Bridge), which requires navigating a steep set of stairs or winding ramps, and walking alongside heavy traffic and sometimes homeless people seeking shelter on the bridge.

“I was born and raised in the Bronx, and I went to Randalls Island once,” said Kevin Crespi, the chief operating officer of a charter school in the South Bronx. “It doesn’t matter where you were in the Bronx, you weren’t going to Randalls Island unless you had a car. A lot of families don’t even know about it.”