Judi W and I did this to celebrate her upcoming birthday. It’s a wonderful community event with families and local business support. There is a kids run and 5K too. It starts out in downtown Danville and parallel 680 until San Ramon and then loop back around on the Iron Horse Trail. It is slightly uphill for the first half and then downhill all the way back.
It was perfect running weather, cool but not cold, didn’t get hot and the sun was out.