Lake Suwa (諏訪湖), is a freshwater lake of murky, green-brown water in the shadow of the Kiso Mountains, Minami-Alps, Nagano. It’s the 24th largest lake in Japan, and the largest in the central Honshu prefecture known for snow, ski and soba. Its location means Suwako spends a significant portion of the year iced over.
Typically for Japan’s seismic character, natural onsen springs up underneath the lake (and of course all around the area). There are beautiful, seasonal, jagged ice mountains all across the lake during the winter months due to the pressure of the warm water pushing up. The locals call these peaks ‘God’s Crossing’ (御神渡り o-miwatari).
In warmer times the lake is popular with water skiers, sightseers on swan-shaped amphibious car-boats, and, seemingly from the architecture (though purpose in these rural parts unknown), passing salarymen staying in functional, cheap business hotels. It has a pleasant grass shoreline in places for picnics but perhaps swimming is a niche pursuit. In fact, swimming could even be dangerous, depending on the type of algae causing the luminous green colour in the water … we are not necessarily recommending this one.
On a cultural note, a trip here can be combined with a visit to Suwa Grand Shrine (諏訪大社). It’s an impressive set of buildings and courtyards dating back to at least the 7th century. It’s spread out over two sites, south and north of the lake.
In mid-August the Suwa Fireworks Festival takes place over the lake, and is known as one of the most impressive in all of Japan.