The park is built inside the actual tunnels of the historic Hosokawa mine, which operated until the mid-20th century.
The theme 'Mu' refers to a legendary lost continent, serving as the narrative foundation for the park's exploration challenges.
The underground temperature remains relatively constant throughout the year, making it significantly cooler than the surface during summer.
Visitors are provided with a 'treasure map' upon entry, which is required to navigate the interactive segments of the mine.
Mikawa Mu Valley is a unique theme park constructed within the abandoned tunnels of the former Hosokawa mine in Iwakuni, Yamaguchi Prefecture. The park features an underground exploration course themed around a mysterious ancient civilization. Visitors navigate through narrow cavern passages while solving puzzles and searching for hidden treasures. The facility emphasizes an immersive atmosphere using light and sound effects throughout the subterranean maze. Beyond the tunnels, the grounds include an outdoor area with camping facilities and recreational activities. The site maintains a cool temperature year-round due to its subterranean location.
The illuminated, mysterious glowing chambers located deep within the main tunnel exploration route.
Wear comfortable, closed-toe walking shoes as the tunnel floors can be uneven or damp.
Bring a light jacket or sweater, as the underground mine tunnels remain cool even on hot summer days.
Plan to complete the indoor puzzle trail before exploring the outdoor recreational grounds.
Don't underestimate the physical activity required; the tunnel course involves significant walking and navigating tight corners that may be difficult for those with limited mobility.
Generally closed on Wednesdays, though this may vary during peak holiday seasons and school vacations.
Avoid running in the narrow tunnel sections and remain mindful of low-hanging rock surfaces.
