The perimeter of Roosevelt Island in New York City is approximately 3.8 to 4.0 miles. The island features a dedicated, paved path known as the Roosevelt Island Greenway, which hugs the waterfront and provides nearly uninterrupted views of the Manhattan and Queens skylines. In 2026, this loop remains a favorite for local runners and cyclists because it is mostly flat and separated from vehicle traffic. A full circuit takes about 75–90 minutes at a brisk walking pace. The route takes you past notable landmarks like the Southend's Renwick Ruin (the old Smallpox Hospital), the Franklin D. Roosevelt Four Freedoms State Park at the southern tip, and the historic 1872 lighthouse at the northern tip. Because the island is only about 800 feet wide at its broadest point, you are never more than a few minutes' walk from the water, making it one of the most scenic urban loops in the United States.