This is a 130-meter-long concrete arch bridge completed in 1937. It appears on the frozen lake surface around January when the dam's water level is low, begins to sink around May as the water level rises, and is submerged at the bottom of the lake by summer. This is the only arch bridge in Japan that appears and disappears with the seasons, which is why it is called the phantom bridge.

■ Late Spring: The 'Spectacles Bridge'
From May onwards, as snowmelt flows into Lake Nukabira, the water level rises. In the early morning, in particular, there is less wind and fewer waves compared to the daytime, so the bridge is reflected on the lake's surface, making the arches appear circular like a pair of spectacles, which is why it is called 'Meganebashi' (Spectacles Bridge).

■ Midwinter: A Solitary Figure on a Snowy Plain
In January, it reappears, breaking through the thick ice of Lake Nukabira, which begins to freeze in December. From that time, it is possible to cross Lake Nukabira on snowshoes to see it. The Taushubetsu River Bridge stands out against the blue of a clear winter sky and the white of the snowy plain.

■ Early Spring: An Impressive Sight
Before Golden Week, the Taushubetsu River Bridge reveals its entire structure. This is also the time of year when the water level of Lake Nukabira is at its lowest. It reveals its full form on the rugged ground of the lakebed. Viewed from the southern shore, the snow-capped Mt. Nipesotsu in the background adds to its splendor.