Kasukabe, Saitama · Underground engineering
Beneath the city, a different scale.
Huge concrete columns rise from the floor of the pressure-adjustment tank at the Metropolitan Area Outer Underground Discharge Channel, often called G-Cans. Its nickname, the Underground Temple, captures the view. Its purpose is practical: this is part of a working flood-control system. Guided visits make an unusual day trip into Saitama.
- Basic Underground Temple tour
- ¥1,200 per person
- Basic tour duration
- About 55 minutes
- Entry
- Reserve a guided tour
- Minimum age
- Elementary-school age
- Access underground
- About 100 steps each way; no lift
- Guide language
- Japanese
Start with the Underground Temple course
The basic course introduces the facility and visits its monumental pressure-adjustment tank. Longer courses add shafts or pumping equipment, each with separate fees and conditions.
Check the stairs and age requirements
All routes require independent walking and about one hundred steps up and down, without a lift. Surfaces may be slippery or dim. Preschool children cannot join. On the basic course, junior-high-school children and younger require an adult, with up to five children per adult.
Prepare for Japanese guidance
Guidance is spoken in Japanese. Bring someone who can understand or interpret instructions, as the operator recommends. Check in at RyūQkan ten minutes before departure and read the course’s clothing requirements.
Keep your itinerary flexible
Flood-control operations take priority. Check current notices before travelling: weather or maintenance may change or cancel tours. The operating-day route can use a raised walkway. Leave enough time for the journey from the station.
Location & access
G-Cans Underground Discharge Channel
RyūQkan, Showa Drainage Pump Station, 720 Kamikanasaki, Kasukabe, Saitama 344-0111
Neighbourhood
Kasukabe / eastern Saitama
From the north exit of Minami-Sakurai Station on the Tobu Urban Park Line, allow about 25–30 minutes to walk roughly 2.3 km. A taxi takes about seven minutes, but taxis may not be waiting at the station. Local bus services are limited; check the official access page. Tour reception is on the first floor of RyūQkan.
Keep exploring
Sources & planning links
- Official courses — fees, duration, stairs, age and language
- Official tour information and latest operating notices
- MLIT — RyūQkan address, walking route and transport
Visitor information reviewed on 13 October 2026. This guide uses published sources. Confirm current hours, prices and availability before visiting.