Phoenix Parks Dept has scheduled a "Silent Sunday" car-free day at South Mountain once a month through the end of the year on the following dates; May 27, June 24, July 22, Aug 26, Sept 23, Oct 28, Nov 18, Dec 23. The more cyclists who show up the more likely they will continue.
For those of you who do not know, Silent Sunday is where personal vehicles will not be allowed on the road past the Activity Complex. This will give the wildlife a break from the fumes and traffic and will give people the chance to enjoy the preserve without the noise or traffic from the road. More information can be found here http://phoenix.gov/parks/hikesoth.html
If you have any questions or comments you can feel free to e-mail or call the phone number listed below.
South Mountain Park / Preserve
10919 South Central Avenue
Phoenix, Arizona 85042
Phone # 602-262-7393
Fax # 602-495-0212
More information can be found here