Matsuri Guide

Name in Japanese and English

• 信州辰野ほたる祭り（しんしゅう たつの ほたるまつり）
• Shinshū Tatsuno Firefly Festival

History

The Shinshū Tatsuno Hotaru Matsuri is the flagship event of Tatsuno, located in the Ina Valley of Nagano Prefecture. It is celebrated as one of Japan’s premier locations for firefly viewing（蛍観賞, hotaru kanshō）. The festival centerpieces are Matsuo-kyō（松尾峡）and the Tatsuno Hotaru Dōyō Park, where thousands of Genji-botaru（ゲンジボタル）light up the summer nights.

Tatsuno’s history is inseparable from firefly conservation. As early as the Taishō era, local citizens and schools initiated efforts to stop mass capture and preserve waterways. After a post-war population decline due to industrialization, the town launched long-term ecological restoration projects, including water quality improvement and the cultivation of kawanina（freshwater snails）, which serve as the fireflies' primary food source. Today, the festival is not just a spectacle but a symbol of a community’s successful harmony with nature.

Location and Date of the Event

• Location: Tatsuno Hotaru Dōyō Park（ほたる童謡公園） and the Matsuo-kyō area.
• Address: 1006-1 Kamihiraide, Tatsuno-machi, Kamiina-gun, Nagano（長野県上伊那郡辰野町大字上平出1006-1）.
• Access: A 15–20 minute walk from JR Tatsuno Station. By car: 10–20 minutes from the Ibukata IC（伊北インター）off the Chūō Expressway. Temporary parking is available but fills up quickly during peak weekends.
• Date: Generally early to mid-June, spanning approximately 9 days.
• Date Type: Variable. The festival is timed to coincide with the peak flight period（発生状況）of the fireflies, which depends on the year's temperature and humidity.

Event Schedule

The soul of the festival is the nocturnal observation walk. The atmosphere is intentionally quiet and dark to allow the fireflies' bioluminescence to shine. Visitors pay a small conservation fee to enter the park, supporting ongoing environmental protection efforts.

During the official period, the park implements one-way traffic（一方通行）to manage the flow of visitors. While the park remains the quiet core, the town center near the station comes alive on weekends with street stalls（露店, roten）and local performances. A notable highlight is the Tatsuno Pikkari Odori, a local dance often performed during the opening festivities.

For the most magical experience, aim for a warm, humid night with low wind and no moon. The fireflies are most active between 8:00 PM and 9:00 PM.

Practical Advice

Photography

Strictly no flash and no bright lights; artificial light kills the firefly experience and disrupts their mating. Tripods are often prohibited during peak times to keep the crowd moving. Use a fast lens (f/1.8 or wider), high ISO, and look for a stable fence or post to lean against.

Weather

While June days are mild, nights in Nagano can be chilly, especially near water. Paradoxically, the best firefly activity occurs in "muggy" weather. Bring a light warm layer and wear closed-toe shoes for safety on dark, potentially damp paths.

Transport

Using the train to JR Tatsuno Station is highly recommended to avoid massive traffic jams and full parking lots. If driving, arrive before 6:00 PM. Many visitors find that staying overnight in local lodging offers the most stress-free experience.

Visitor Tips

Avoid the first Saturday if you want to skip the heaviest crowds. To see the maximum number of fireflies, check the official firefly count updates on the town's website. Walk slowly, speak in whispers, and keep your phone screen brightness at its lowest setting.

What to Bring

Cash (for the entry fee and food stalls), insect repellent (for mosquitoes, not fireflies!), a power bank, and a small red-light flashlight (which is less disruptive to eyes and fireflies) if you must use a light on the path.

Sources & References

• Tatsuno Town Official: Matsuo-kyō & Hotaru Dōyō Park

  Site presentation, peak viewing times, and photography rules.

• Tatsuno Town Official: History of Firefly Protection

  Detailed timeline of conservation efforts and environmental research.

• Nagano Inadani Tourism: Japan's #1 Firefly Festival

  Tourism context and guide to ideal weather conditions for viewing.