West Miner Street is the part of Yreka that justifies leaving the interstate. The old storefronts, plaques, and civic buildings give the town a visible Gold Rush spine, with enough surviving fabric to make a short walk worthwhile.
Do not expect a museum village. This is still a working small-town downtown, which is part of its appeal. Go slowly, read the historical markers, and look for the way the street bends around the old commercial core.