There have been many hillclimbs that never happened, usually because the permission for the event wasn’t granted. Reasons often cited for the local governments refusal was access limited for locals, bad example for young drivers, local drivers “racing and practicing” on the road, and disruptive noise. Lack of money and insurance problems are cited also.
Below is a list of events that I found some information on, but then could never find results or any indication that it actually happened. Some we know never happened, others I couldn’t find a specific cancellation.
Mount Shasta, California
Reddington Road ,Arizona
Freshwater Road, California
Sandia Road, New Mexico
Silver Mountain, Idaho
Sierra Cross Kilometer Climb, California
Woodacre, California
Coal Creek, Washington