Loretta Lynn is the subject of a new documentary titled Loretta Lynn: Still a Mountain Girl, which premieres March 4 at 9PM on PBS. In a trailer for the film, Miranda Lambert and Sheryl Crow share how Lynn broke down the doors for women in music.

"Loretta always said exactly what she was going through right then in her music, and that's why it resonates with us," Lambert says in the nearly three-minute clip.

Crow emphasizes the impact Lynn had on females in music everywhere.

"I definitely couldn't be doing what I'm doing unless she had broken down those barriers and had been a songwriter for all of us," she states.

Lynn herself comes from humble beginnings, and says that she never dreamed up a career like she's had. The trailer includes clips of her performing at the Opry, being recognized by President Obama and interviews with the music community.

"I never thought of anything like this when I was a kid," Lynn says. "Growing up in Butcher Holler, that's where you'd stay I thought."

Lynn will be featured as part of Women's History Month during the 30th anniversary season of the American Masters series. The film premieres on March 4, which is also the day that Lynn will release her new album Full Circle, her first studio album in over 10 years.

Still a Mountain Girl features never-before-seen home movies, performances and photos of Lynn. In addition to interviews with Lynn, Lambert and Crow, Lynn's family, friends and musicians including Jack White, Willie Nelson, Garth Brooks, Trisha Yearwood, Reba McEntire, Sissy Spacek, Bill Anderson and producer John Carter Cash will also be featured.

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