We caught a train out, and walked the remaining 2km to the facility.
Great to see you can get onto the floor now !
http://ninjito.com/2006-07-04 http://ninjito.com/images/2006-09-22/qx-pano-18.jpg
https://en.wikipedia.org/wiki/Metropolitan_Area_Outer_Underg...
The guide himself was free, a nice older gentleman who used to be some sort of government liason. He insisted on taking a taxi for the 2 miles from the train station to the tour though, which was pricey. But I didn't have much of a choice (despite a whole face-saving false choice he offered of walking vs taxi that was deeply emblematic of a certain strain of Japanese cultural weirdness).
You might also enjoy some of my other drain exploration shots from stateside:
Which is likely why it's a common backdrop for many a Tokusatsu shows[0]. Every season of Kamen Rider[1] -- and likely Super Sentai[2] as well; I'm not sure since that's too juvenile for my taste -- is all but guaranteed to have at least one episode filmed there.
[0] https://en.wikipedia.org/wiki/Tokusatsu
http://www.lucashayas.com/journal/2018/11/18/maoudc
It cost about 80 bucks all told and was a bit of an ordeal to organize (you need a fluent Japanese speaker), but was definitely an experience. It was a little disappointing in how limited our tour was. I get the sense that they've narrowed down the area you can wander since opening. Still, I've explored storm drains in the US quite a bit and this was a whole different level.