The City of Fog
In the summer, warm air from the Pacific Ocean forms fog as it moves north and reaches the colder coastline of eastern Hokkaido. Kushiro is known as the “city of fog” for its frequent foggy days in summer. The city is a major port, and low-visibility conditions are hazardous for shipping. For this reason the Kushirozaki Lighthouse was built in 1891.
Initially, the lighthouse had no audible fog warning system. But in July 1922, Crown Prince Hirohito (1901–1989), who later became Emperor Showa (reigned 1926–1989), visited Kushiro during a typical heavy fog, and recommended that the city install a foghorn at the lighthouse. The foghorn was completed in 1925. The trumpet-shaped part, known as a “sounder,” amplified compressed air to create a low-frequency warning tone. This was replaced by an electric version in 1962. The electric foghorn was decommissioned in 2010, after advancements in ship navigation equipment made foghorns unnecessary.