Join Mountainside Fitness today and get your first 30 Days Free + $0 Enrollment + 2 Peak Amenities OR 2 FREE Training Sessions! Offer ends soon, sign up for a Membership or Download a Free 5 Day Pass to check us out at mountainsidefitness.com. We offer state-of-the-art equipment, group fitness classes, appointment free childcare, towel service, cardio and access to all 21 Clubs in the Valley.