The Narusawa Ice Cave, or Narusawa Hyoketsu, is a fascinating lava tube located at the eastern edge of the Aokigahara Sea of Trees, a forest at the base of Mount Fuji. Formed by a massive eruption of Mount Fuji in 864 AD, this 153-meter long cave maintains an average temperature of around 0 degrees Celsius year-round. It's designated as a national natural monument and is known for its unique ice formations, including icicles and ice pillars, which are particularly impressive from March to August.
Visitors consistently praise the cave for its cool temperatures, making it a refreshing stop during hot summer days. Many find the experience of navigating the narrow, low passages adventurous and exciting, especially the sections where one must bend or even crouch to pass. The provided helmets are universally appreciated and considered essential due to the low ceilings. Reviewers often highlight the unique geological formations and the opportunity to see ice year-round as key draws. However, a recurring theme in reviews is the cave's short duration, with most visits lasting only 10-15 minutes. Some visitors express disappointment, particularly if they expect an extensive cave system or large, naturally formed icicles, as some ice formations are described as man-made or less spectacular than anticipated, especially outside the peak ice season.
To make the most of your visit, wear comfortable, non-slip shoes as the floors can be wet and slippery, and the stairs are steep. Bringing a light jacket or windbreaker is advisable, even in summer, due to the consistently cold temperatures inside. Tall individuals should be prepared to crouch significantly in certain sections. Many visitors recommend combining the Narusawa Ice Cave with a visit to the nearby Fugaku Wind Cave, as a joint ticket is often available and the two caves are connected by a walking trail through the forest. The best time to see impressive icicles is from March to August; visiting between November and January might result in fewer ice formations.
The Narusawa Ice Cave is easily accessible by public transport. It's a stop on the sightseeing buses that circulate around the Lake Kawaguchiko area. Maps and affordable bus passes can be obtained at Kawaguchiko Station. If driving, there's a large parking lot available in front of the ticket center. The cave is located directly off National Route 139.
Common complaints revolve around the short duration of the visit and, for some, the perceived lack of natural ice formations. To mitigate disappointment, manage expectations regarding the cave's size and the scale of the ice. Focus on the unique geological experience and the refreshing coolness. Be aware that the cave is not suitable for individuals with mobility issues, claustrophobia, or very young children due to the steep stairs, narrow passages, and required crouching.
