The Grammy Museum is paying homage to some of the most defining moments in Johnny Cash's career, as well as the photographer who captured them. The photos from Cash's prison concerts in the late 1960s, taken by legendary music photographer Jim Marshall, come to life at the Grammy Museum's latest exhibit, The Prison Concerts: Folsom and San Quentin (Jim Marshall’s Photographs of Johnny Cash).

Cash famously performed at Folsom Prison in 1968, and one year later at San Quentin State Prison. Marshall was requested by Cash to document the events, immortalizing the experience by capturing the famed middle-finger shot; as well as a photo of Cash shaking the hand of inmate Glen Sherley, who wrote a song titled "Greystone Chapel" that the iconic singer performed during the Folsom Prison concert.

Visitors will also see color and black-and-white candid shots from the performances, along with the famous photo of Cash stepping off the bus at Folsom Prison.

"There was no restriction. There was [no one] telling me you can't do this, you can't do that, you can't go here, you can't do that. That was it. I was there taking pictures. That's the magic," the late Marshall previously stated in an interview.

The performances were significant to Cash both personally and professionally. He created two live albums based off of his appearances at Folsom Prison and San Quentin, with both reaching the top of the country and pop charts.

He also spent years advocating for prison reform. “He thought the prison system was broken, because it wasn’t fixing anybody,” Cash's friend and historian Mark Stielper told the Washington Post"[He] made mainstream society aware of the need for prison reform. There was nobody at his level of prominence who was doing the same thing."

The Prison Concerts: Folsom And San Quentin (Jim Marshall’s Photographs Of Johnny Cash) is on display at the Grammy Museum in Los Angeles until Feb. 24.