Mountain Dell ski area is a fee area operated by TUNA and has 12 km of trails that are groomed daily. TUNA employs a head groomer who oversees a volunteer grooming staff of over 20 members. Those groomers create and maintain pristine track used by members and non-members in the Salt Lake and Park City area.

Mountain Dell serves as the training ground for the NCAA Division 1 championship Utah Utes ski team as well as programs for all ages.

Users can pay a daily fee or purchase a season pass here.

TUNA also sets track on SR65, aka East Canyon Road, about once a week in the winter.