Australia has a town where almost half the population live under ground, has an underground church, the national gem stone of Australia is mined there, has an aboriginal name meaning "white man in a hole". Early living conditions were harsh with every person only entitled to 60 litres of transported water per week. Now the town water supply is underground pumped from over 24 km's away. This now modern town is a popular tourist destination and has developed a multi-million $ mining industry.
What town am I?