PHOTOS: 4th Annual ACM Party for a Cause – Day 1

The 4th Annual ACM Party for a Cause kicked off Friday (April 1) with a star-studded all-female lineup headlined by Carrie Underwood. 

PHOTOS: 4th Annual ACM Party for a Cause – Day 1
Carrie Underwood, Photo by Larry Busacca/Getty Images for ACM

The 4th Annual ACM Party for a Cause kicked off Friday (April 1) with a star-studded all-female lineup. The event, which is taking place at the Las Vegas Fairgrounds through Sunday, April 3, featured two stages and performances by Kelleigh Bannen, Lauren Alaina, Jana Kramer, Brandy Clark, Cam, Maddie & Tae, Kelsea Ballerini, Kellie Pickler, Martina McBride, and Carrie Underwood.

Fans were treated to a handful of special moments, including ACM CEO Bob Romeo surprising Kelsea Ballerini with her first ACM Award after her set, a surprise appearance from reigning ACM Female Vocalist of the Year Miranda Lambert, who joined Carrie Underwood for “Something Bad,” an all-star performance of “Before He Cheats” with Kelleigh, Lauren, Jana, and Kellie joining Carrie on-stage, and Romeo presenting Underwood with the ACM Lifting Lives Gary Haber award.

Check out photos from day one of the 4th Annual Party for a Cause below.

Kelleigh Bannen, Photo by Isaac Brekken/Getty Images for ACM

Kelleigh Bannen, Photo by Isaac Brekken/Getty Images for ACM

Lauren Alaina, Photo by Isaac Brekken/Getty Images for ACM

Lauren Alaina, Photo by Isaac Brekken/Getty Images for ACM

Jana Kramer, Photo by Rick Diamond/Getty Images for ACM

Jana Kramer, Photo by Rick Diamond/Getty Images for ACM

Brandy Clark, Photo by Isaac Brekken/Getty Images for ACM

Brandy Clark, Photo by Isaac Brekken/Getty Images for ACM

Cam, Photo by Christopher Polk/Getty Images for ACM

Cam, Photo by Christopher Polk/Getty Images for ACM

Maddie & Tae, Photo by Christopher Polk/Getty Images for ACM

Maddie & Tae, Photo by Christopher Polk/Getty Images for ACM

"LAS VEGAS, NEVADA - APRIL 01:  Academy of Country Music CEO Bob Romeo (L) and singer Kelsea Ballerini pose with her New Female Vocalist award at the 4th ACM Party for a Cause Festival at the Las Vegas Festival Grounds on April 1, 2016 in Las Vegas, Nevada.  (Photo by Rick Diamond/Getty Images for ACM)"

Academy of Country Music CEO Bob Romeo (L) and Kelsea Ballerini, Photo by Rick Diamond/Getty Images for ACM

Kellie Pickler, Photo by Isaac Brekken/Getty Images for ACM

Kellie Pickler, Photo by Isaac Brekken/Getty Images for ACM

Martina McBride. Photo by Larry Busacca/Getty Images for ACM

Martina McBride. Photo by Larry Busacca/Getty Images for ACM

Carrie Underwood. Photo by Isaac Brekken/Getty Images for ACM

Carrie Underwood. Photo by Isaac Brekken/Getty Images for ACM