I apologize for not reporting this massive craft years ago.

My ex wife son and his 11 year old friend were with us.  We were going home after seeing the movie at the drive in theater (Disney movie).  We were on the freeway overlooking the city of New Hall, Ca.  The craft was enormous.  It looked like a floating city.  
By the time we went under the freeway overpass we were less than one eighth mile from driving directly under the craft.  It was bigger than a aircraft carrier.  As we came under the freeway overpass there was 3 Ca. highway patrol cars and 3 or 4 private cars parked along the road into the town.  The strangest thing about the sighting (except the humming sound)  We never talked about the sighting until a few months ago.  I had asked my son if he remembered the sighting.  He not only clearly recalled it.  He called his Mom, and she remembered it exactly as we did!