14 June 2011 (-1 in time zone):

Another guy and I ended up visiting the Dwarves Cave. The guide told us that this lava tube led all the way to the coast, but didn't take us that far in. We stopped at an underground pool that we jumped in. The cave continued past the pool.

Rough notes:
http://mandarinmanmarktravelnotes.blogspot.com/2011/06/2011-nz-to-sf-day-32.html