This mountain can only be visited from Mid April to Mid November once the road is open, you can only go with the organised tour but it is worth
This was during Golden Week and we got told that the walls go up to 16m high. when comes the time, the Toyama prefectures has 2 huge machines that create the road you see, it was a sunny day, we were at 5 degrees. we loved it
It seems that Taiwanese love the place but other than that, it is mostly Japanese tourists.