Asari Dam 朝里ダム

A 73.9-meter gravity dam completed in 1989 (Heisei 1), located in the upper Asari River valley in Otaru. The reservoir it creates, Lake Otarunai, serves as an important water source for Otaru. The Asari Sky Loop Bridge — a gracefully curving loop road providing access to the dam site — arches elegantly over the reservoir. Its harmonious integration with the surrounding mountain scenery earned it the Otaru City Urban Landscape Award.

The area is particularly celebrated for its autumn foliage, which typically peaks in mid to late October, when the mountains surrounding the loop bridge and reservoir blaze with vivid shades of red, yellow, and orange, creating a breathtaking panorama. A lakeside walking path allows for a leisurely stroll through the scenery at any time of year. While not widely known outside the region, the dam and its surroundings are a favorite scenic drive for locals.

The adjacent "Asari Dam Memorial Hall" features exhibits on the dam's construction history and Otaru's water supply system; during opening hours, visitors can also tour the interior of the dam structure. It makes a rewarding detour when combined with Otaru's other well-known sights.