Gold was mined from quartz bodies at Ballarat East from the 1850s until closure of the last mine in 1917. The average depth of mines was about 350 m.
Ballarat Goldfields Limited (BGL) carried out diamond drilling from surface between 1985 and 1987 which proved the continuation of gold-quartz mineralisation beneath the old mines.
During 1989 an underground development program was commenced to access the mineralisation for detailed exploration. The program included two simultaneous shaft developments. These were known as B2 shaft and Llanberris No.1 shaft.