Yes, you can absolutely walk the entire length of Roosevelt Island in New York City, and it is a highly popular activity for both locals and tourists in 2026. The island is approximately 2 miles long and just 800 feet wide, and a full loop of its perimeter takes about 60 to 90 minutes at a leisurely pace. The "Roosevelt Island Greenway" provides a paved, waterfront path that encircles the island, offering stunning views of the Manhattan skyline to the west and Queens to the east. A complete walk usually starts at the southern tip at the Franklin D. Roosevelt Four Freedoms State Park (near the iconic ruins of the Smallpox Hospital) and ends at the northern tip at Lighthouse Park. The island is mostly flat and pedestrian-friendly, with plenty of benches and green spaces along the way. While you can take the "Red Bus" for free to navigate different points, walking is considered the best way to see the island's unique sculptures, historic landmarks, and the futuristic Cornell Tech campus.