Fireflies like to have pristine bodies of water for breeding and Nagano is blessed to have many such locales where you can watch ‘hotaru’ (as they are known in Japanese) light up at night and dance around like little fairies.  Here are four of Nagano’s best-known hotaru spots.

Tatsuno Town’s Hotaru Festival

The town of Tatsuno prides itself in its preservation of its wetlands around the Tenryu River and the people have worked hard to make the environment as friendly as possible to fireflies.  Their effort has paid off and in fact the town is almost synonymous with fireflies.  The result is one of the prefecture’s most famous festivals, the Tatsuno Hotaru Festival which has been held every year for over 7 decades.  The festival usually takes place for a week in the middle of June at Hotaru Doyo Park, approx. 1 km from Tatsuno Station.  Besides the multitude of fireflies in the park and nearby Matsuo Ravine, there are food vendors and even taiko drum performances.  The best time to see the fireflies glowing in the dark is from 8 to 9pm on hot and humid nights.

Sakura Zutsumi Hotaru (firefly) Canal in Ueda City’s Shimoshiojiri neighborhood

Along a cherry blossom tree-lined side canal of the Chikuma River is another location with just the right conditions for fireflies to breed.  For around 2 weeks in the middle of June, several hundred fireflies can be seen around the banks of the canal.  The peak viewing time is from 7:30 to 9:30pm.  The park is located 1.3km west of Nishi-Ueda Station on the Shinano Railway line.  There aren’t any shops or vendors, but there is a small display with explanations of how the neighbors are protecting the pristine environment of the nearby wetlands.

Kitsunezuka in Ueda City’s Maruko district

Behind a grocery store and strip mall along Route 152 in Ueda City’s Maruko district is a small ravine named Kitsunezuka.  The local residents work hard to maintain the natural state of the Shiozawa creek bed and every year, usually for around a week at the end of June, hundreds of fireflies come out at night for their flickering mating dance.  The best time to see glowing show is from 7:30 to 9:30pm.  The Kitsunezuka Hotaru no Sato park features a small footbridge over the stream so you can experience the fireflies both above and below you.  The location is 1km south of Oya Station on the Shinano Railway line.  A few food vendors add to a festive feel.

Hakuba Valley’s Lake Aokiko

From mid-July to mid-August, fireflies can be seen dancing about the spring-fed Lake Aokiko in Omachi City.  Outdoor tour outfitters offer guided night-time canoe tours on the lake.  You can catch a shuttle from Hakuba Village, grab a paddle and ride in a 10-person Voyageur Canoe to row into the natural habitat of the fireflies, where they dance overhead and around the boat.

Shiga Kogen’s Ishi-no-Yu

Boasting Japan’s highest altitude (1650m) firefly breeding ground, Shiga Kogen’s Ishi-no-Yu has been designated a National Natural Monument.  The Iwakurasawa stream is fed by natural hot springs creating the perfect environment for fireflies.  Due to the remote location there is no public transport access.  When coming by car, there is a parking lot off to the right of Route 292 just above Kido Pond.  From the parking lot Ishi-no-Yu is a 10 minute walk.  Firefly season is from the end of July to the end of August, with photography possible during the month of August.

For all firefly spots, please refrain from using flash photography and/or bright smartphones, as the lights startle the fireflies and disrupt other people’s pictures.  Also, especially for at Lake Aokiko and Shiga Kogen, be sure to dress warmly.