Mamon Mine is the mine in the town of Mamon. Excavation took place in the mine, as materials to make gun-powder were plentiful. However, the miners eventually dug to deep, and poisonous fumes from Estark's lair began to seep out. The fumes would soon spell the end of the town.
In Chapter 4, Meena and Maya goes in to search for a powder keg. Mamon Mine is revisted in Chapter 5 as Estark is fought in the mine's farthest depths after the digging from the miners leads to his base being uncovered.