The swing span is variously cited as being or long. The swing span's trusswork consists of concave chords running along the top. The chords taper up toward a square section in the center of the span, which is topped by four finials. The swing span can be rotated around a tower below the center of the deck, which in turn is on the small masonry island. The rotating tower is about in diameter and is anchored into the bedrock beneath the Harlem River. The swing span is supported by three piers, one in the center of the river and one on each bank; these piers are made of concrete and faced with ashlar. At either end of the bridge's approach spans are concrete ramps with walls made of granite ashlar.