This mining location can only be accessed once you have completed Between a Rock... quest. It the BEST spot in the game to mine gold, with around 146 rocks and veins. This is because the entrance room has an abundance of gold rocks and veins, allowing you to get a load of gold very quickly. Once you have your gold exit the mine and head east to the river. Here you can ask a dwarf to bank it for you; although he does take about 3-6 ores off you to cover costs. Wear a Ring of Charos(a) to reduce the amount of gold ores you pay him.

To be able to get through the rock, you must be wearing a gold helmet, which you obtain during the quest. Speak to Dondakan, and ask him to shoot you through the wall. To leave, either logout, or take off your gold helmet.