Grass Valley, Calif.— On Saturday, August 29th, from 11 a.m. to 4 p.m., participate in a treasured local tradition at Empire Mine State Historic Park! Highwater & The Kin – Credit Casey GarrottoMiner’s Picnic began in 1895 as a benefit event for the families of deceased local miners. Witness the traditional reenactment of an 1888 mine explosion, with Grass Valley Fire Department’s vintage fire truck responding to treat the “injured miners.” © 2025, California State Parks. RAIN OR SHINE Where: Empire Mine State Historic Park, 10791 East Empire Street, Grass Valley CA.