Lake Suwa and Yatsugatake

This 4K camera looks across Lake Suwa toward the Yatsugatake range. The lake is the largest in Nagano and sits at about 759 metres in the Suwa basin, a low point on the Fossa Magna where the geology of eastern and western Japan meets.

In hard winters the lake produces the omiwatari — a pressure ridge that forms when the ice sheet expands and buckles, throwing up a jagged line right across the surface. It has been recorded by the priests of Suwa Taisha for centuries, and the records are now used as a long-run climate dataset. It does not form every year, and in recent decades it has failed more often than not.

The other thing Suwa is known for is the Onbashira festival, held every six years, in which enormous fir trunks are cut in the mountains and dragged down to the shrines. Outside those years the basin is a quiet place of hot springs, precision manufacturing and lake weather.