The inclined shaft connecting the bottom of Lake Yamamoto to Golgotha is by far the longest part of the complex, but it need not have a very great diameter: just big enough for a single worker to worm his way up to the end and operate his drill. Before the lake is created, Goto Dengo has a crew dig the extreme upper end of that shaft, tunneling out and down from the riverbank with a dip angle of some twenty degrees. This excavation continually fills up with water—it is effectively a well—and removing the waste rock is murder, because it all has to be hauled uphill. So when it has proceeded for some five meters, Goto Dengo has the opening sealed up with stones and mortar.