Knoxville (WVLT) - You only turn 21 once, right?
US Cellular is celebrating its 21st birthday with a treat for you.
This morning, the wireless carrier announced it will host a rock music festival, for free.
The all day celebration will feature Lifehouse, Joan Jett and the Blackhearts, along with Knoxville's own, Jag Star.
The festival is April 28th at World's Fair Park. Festivities run from 2:30 to 9:30 pm.
For information on how to get your free ticket voucher, check out www.uscellularroxknox.com.