Shiraito Falls, Waterfall in Nagakura, Karuizawa, Japan

Shiraito Falls is a waterfall in Nagakura, Karuizawa, that extends 70 meters across and consists of hundreds of fine lines of water flowing over a curved rock wall. The water comes from underground springs that seep through volcanic rock layers and spread across the surface into a wide curtain.

The falls owe their existence to two volcanic events: the collapse of Mount Kurofu around 24,000 years ago, which left a debris-avalanche deposit, and the Tenmei eruption of Mount Asama in 1783, which laid down a pumice layer. Groundwater from the Asama massif emerges where that pumice meets an impermeable lake clay, and the semicircular front and pond were shaped in the early Showa era.

The name Shiraito, "white threads", comes from the spring water falling in several thin lines like silk, unclouded and steady in any weather. In summer the town and the Shiraito Highland Way company project images onto the falls at night; in winter the falls and snow are lit up.

The falls lie along the Shiraito Highland Way linking Karuizawa with Kita-Karuizawa, at an elevation of 1,260 m. From Karuizawa Station take the Kusakaru Kotsu bus toward Kita-Karuizawa for about 23 minutes and get off at Shiraito-no-taki, then walk about 5 minutes. Because the water comes from underground seepage, the flow stays fairly constant and does not muddy after rain. The falls face a pond held by a dam, with a stepped cascade below it.

The many separate lines of water do not come from a stream or river but emerge directly from the rock itself. Each line marks a spot where underground water has found its way to the surface.