The highest natural point within the city limits is in the Beverly neighborhood at 41°42′12.5″N 87°40′37″W﻿ / ﻿41.703472°N 87.67694°W﻿ / 41.703472; -87.67694 at 672 ft (205 m).[1] In pioneer days, this hill was called Blue Island, so named because at a distance it looked like an island set in a trackless prairie sea. In fact, it and the nearby Stony Island were both islands in Lake Chicago as it receded. On the North side, the diagonals Clark Street and Ridge Boulevard run along ridges that were once sandbars in the Lake.