Onaka Seto West Lighthouse

The Onaka Seto West light was a 9.5-meter white concrete post situated atop a 1-story concrete equipment room, which itself was mounted on a square concrete pier. Established and first lit in 1971, this structure guided vessels near the southeastern tip of Io Shima, off the coast of Nagasaki. For almost forty years, it provided navigational assistance in the waters close to the port of Nagasaki. The light became inactive in 2010, with its deactivation attributed to nearby bridge construction. It was subsequently removed in 2012.

Why it matters: The deactivation of Onaka Seto West light highlights how infrastructure development, such as bridge construction, can lead to the obsolescence of traditional navigational aids.