Inada stone, quarried here, is famous for its high content of pure white feldspar, making it one of the whitest granites in the world.
The quarry has been active for over 100 years, with some excavation pits reaching depths of over 60 meters below ground level.
The flooded pits were originally created by the natural accumulation of groundwater after mining activities reached the water table.
The granite found at this site is estimated to be approximately 60 million years old.
Large blocks extracted from this quarry are still carved using traditional and modern wire-sawing techniques on-site.
The site occasionally hosts photography exhibitions and film crews due to the unique, otherworldly texture of the exposed rock faces.
Ishikiri Sanmyaku, known as the 'Grand Canyon of Japan,' is an active industrial granite quarry located in Kasama, Ibaraki. The site features a massive open-pit excavation site that has been producing Inada stone since the Meiji era. Visitors can view a flooded quarry pit that creates a distinct emerald-blue reflection against the stark white granite walls. The granite extracted here is historically significant, having been used for iconic structures such as the Tokyo Station Marunouchi building, the Diet Building, and the base of the Supreme Court of Japan. The facility operates as an industrial site where guided tours provide access to restricted areas. Visitors can witness the raw scale of rock extraction and the mechanical processes involved in stone cutting. The landscape is characterized by vertical cliff faces and deep, man-made basins. The site has been repurposed for tourism while maintaining its core mining functions.
The observation deck overlooking the 'Chizu' (map) pond, which offers a panoramic view of the flooded quarry basin.
Wear sturdy, closed-toe walking shoes as the ground is uneven, dusty, and consists of loose gravel.
Bring a hat and sunscreen as there is minimal natural shade within the quarry basin.
Check the official website for guided tour availability, as self-guided access is limited to specific zones.
Do not attempt to climb the quarry walls or touch the machinery, as it is a functioning industrial work zone.
Occasionally closes during periods of extreme weather or heavy rain for safety reasons.
Stay strictly within designated paths and roped-off areas; do not approach the cliff edges or equipment.
