The Brooklyn Bridge holds two structural eras in a single figure: masonry towers pierced by Gothic arches and, hung from them, the first bridge cables ever spun from steel wire rather than iron, doubled by a fan of inclined stays that gives the span its characteristic web. Designed by John A. Roebling, who died in 1869 months before the ground was broken, and completed under his son Washington — incapacitated by caisson disease and relaying instructions through his wife, Emily Warren Roebling — it opened in 1883 with a river span of 1,595 feet (486 m), then the longest in the world, and a broad promenade raised above the roadway. The elevation isolates the tower at the scale where both registers read at once: the mass of the cut stone, and the geometry of everything that passes over it.