Road to Miles trailhead
Most of the road through the mine is graded. There's a rocky section just before the southeastern end of the Haunted Canyon trail that requires a mid-clearance car and careful wheel placement. Later sections are somewhat washed out for short stretches but may be driveable by mid-clearance cars. A car with one adult may make it while one heavily loaded with 4 adults might not. High clearance is recommended--at least for your first trip.