Each spring, Yamagata Prefecture's famous Shirakawa Lake Submerged Forest becomes even more enchanting after dark with its annual illuminated light-up event.
Held at Shirakawa Lakeside Park in Iide Town, the seasonal event showcases one of Japan's most unusual natural sights: a forest of white willow trees appearing to rise directly from the water as snowmelt from the Iide mountain range floods the lake each spring.
For 2026, the event dates are April 18th & 19th, April 25th - May 10th, and May 16th & 17th, from 18:30 - 21:00.
The surreal landscape has gained growing attention in recent years, including mention in National Geographic's Best of the World 2026 feature as one of Yamagata's standout natural attractions.
During the light-up event, warm LED lighting transforms the flooded forest into a tranquil nighttime art installation, illuminating key sections of the lake while preserving the area's peaceful atmosphere. The result is a dramatically different experience from the daytime view, with glowing trees reflected against the dark water for an almost dreamlike effect.
Visitors can also stop by the seasonal Submerged Forest BAR, which serves drinks and snacks beside the illuminated lake, with seating positioned for prime views of the scenery.
Because the submerged forest is only visible for a limited period each spring before water levels recede, the illumination has become one of Yamagata's most sought-after seasonal events for photographers, nature lovers, and travelers looking for lesser-known spring destinations.
