I know there are tunnels in New Zealand and for some reason (the name is relevant) I keep coming back to the Pike river mine disaster of 2010. I have seen somewhere a global map of tunnels and from that map came to the conclusion that there were tunnel entrances on the same area of coast as the Pike river Mine, and also around Christchurch directly across on the opposite coast of the south island. Three months after the Pike River Mine disaster was the major earthquakes in Christchurch. Bearing in mind that New Zealand is a colonized country.
I don't know - why does this keep playing on my mind?

http://wakeupkiwi.com/feature-articles.shtml

https://en.wikipedia.org/wiki/Pike_River_Mine_disaster