Guida
Hotaru Doyo Park, situated in Matsuo Gorge within Tatsuno Town, Nagano Prefecture, is an ideal destination for observing fireflies. This area once possessed the perfect natural environment for Genji fireflies, but faced challenges due to environmental changes. However, through the town's proactive environmental conservation efforts—including the maintenance of water channels and the creation of streams using fallow fields—the area has been revitalized as a sanctuary for fireflies. The park is divided into two distinct areas: the 'Fureai Zone (Hiraide side)' and the 'Small Creatures Zone (Shimotatsuno side),' both offering a rich and diverse natural environment.
The natural environment of Matsuo Gorge was designated as a prefectural natural monument in 1935. However, during the 1950s and 60s, the firefly population declined significantly due to industrial and domestic wastewater and the use of agricultural chemicals. In response, Tatsuno Town undertook continuous efforts to protect the water quality and restore the habitat, including water channel improvements, grass cutting, and sediment removal. These dedicated conservation efforts have successfully brought the fireflies back, allowing the park to serve as a vital 'home for local wildlife.'
The greatest spectacle at the park is the dance of the fireflies from early to mid-June. The most intense activity occurs on warm, humid nights with minimal moonlight, typically between 8:00 PM and 9:00 PM. Watching the glowing Genji fireflies against the backdrop of the carefully maintained streams and natural scenery is a truly unforgettable experience. Additionally, the park features playground equipment, making it a wonderful place for families to enjoy nature together.
The best season for firefly viewing is from early to mid-June. For the best experience, aim to visit between 8:00 PM and 9:00 PM. While the visibility depends on weather and temperature, choosing a night with minimal moonlight will enhance the beauty of the glowing lights. While the park offers various seasonal charms, a nighttime visit during this specific window is highly recommended for firefly enthusiasts.
Visitors can enjoy strolling around the well-maintained water channels and streams to feel the richness of the natural environment. During the firefly season, the quiet night atmosphere provides a unique opportunity to experience a natural light show. During the day, the park is also used as a recreational space for families, thanks to the various play areas available for children.
The park is surrounded by the beautiful Matsuo Gorge, an area known for its scenic beauty and ongoing commitment to environmental preservation. The entire Tatsuno Town area works in harmony with nature, allowing visitors to enjoy a landscape that reflects a deep respect for the natural world.
As you will be walking at night, we recommend wearing comfortable shoes and bringing a light or flashlight for movement. However, to minimize the impact on the fireflies, please be mindful of your surroundings. If you wish to use the parking lot or facilities for specific events, please note that a prior application and fee may be required. Please check local guidelines in advance.