Mountainside Fitness is one of the friendliest gyms in town that still offers free towel service after 23 years. We would like to thank our members for supporting us from the beginning and making us what we are today. Mountainside Fitness is the largest locally owned health club chain in the state of Arizona. With ten fitness centers across Arizona and future plans to expand we expect to exceed over 65,000 active members. Come join our community today.