The Turtle Tower stands on a small rocky islet near the center of Hoan Kiem Lake — not on the island where Ngoc Son Temple is, but a separate, smaller outcrop further south that is not accessible to visitors. The tower itself was built in the early 19th century during the Nguyen dynasty; it's a two-storey structure of yellow-plastered stone with arched windows, modest enough in itself but unmistakable in the lake's geography. It appears in the background of almost every photograph taken from the lake's edges.
The tower is visible from the walking paths around the lake, from the The Huc Bridge leading to Ngoc Son Temple, and from the rooftop cafe at Cafe Pho Co on Hang Gai Street. Because it sits on an inaccessible islet, visitors relate to it entirely from a distance, which may actually enhance its effect: it's always there, always slightly separate, always reflecting on the water around it. The name and the legend connect it to the giant turtle whose preserved remains are in Ngoc Son Temple across the water — though the tower predates the most famous version of the Le Loi sword story by several centuries.