Matthew Terrell spent last year fixated on all things Keith Haring, an iconic pop artist of the 1980s.

Terrell read biographies and art books and watched grainy YouTube documentaries about the late famed artist, who generated some of the most recognizable art of our time before dying of AIDS at age 31.

While leafing through one of Haring’s journals last summer, Terrell noticed a notation about a mural painted at Grady Memorial Hospital in 1988. It featured Haring’s seemingly simple cartoonish style — a happy elephant, a bright daisy and a smiling snail.

But the hospital’s pediatric waiting room, where the mural was displayed, had moved a few years later. What happened to the mural? Did it move, too? Was it painted over?

Terrell, 28, a freelance photographer and writer in Atlanta embarked on a mission to find out and chronicle the mural’s fate.

He started with a call to Children’s Healthcare of Atlanta (which has long managed Grady’s pediatric services) and which is now housed in a separate building across the street – Hughes Spalding.

Chrissie Gallentine, who works in PR at Children’s Healthcare, told Terrell the cheerful mural was torn down in 1991. After the demolition a new laboratory was built on the site, while Grady’s pediatrics unit moved to Hughes Spalding.

Terrell began to think the most he would get is a photo of where the Haring mural once stood.

But Gallentine continued to ask around and learned that Bill Auten, Director of Facilities at Children’s Healthcare’s Hughes Spalding hospital not only knew about the Haring mural but was saving a piece of it in his personal storage unit.

It turned out a chunk of the wall — showing the happy, bright orange snail — had been saved in a Hughes Spalding basement in 1993. When the hospital needed to clear out the room, the snail had to go. Auten, who had recently starting working at Hughes Spalding as a business manager, couldn’t bear tossing the piece of art and history.

Auten, who admits to hoarding tendencies, wrapped a pale blue blanket around the snail piece and moved it to his own condo storage space Years went by. Auten rented the condo but kept the storage space for his stuff, which also included everything from high school memorabilia to an old sink.

The snail was part of a mural that stretched across a wall and was a mix of plaster and concrete with heavy wires embedded into the wall. Saving that piece, Auten, must have required a special saw because cutting the piece was like “cutting through a chain link fence.”

“I figured somebody would want it someday but I kind of forgot about after 20 years,” he said.

So last month, Autin loaded up the hidden Haring into the trunk of his car and headed to Hughes Spalding for Terrell to take a look.

Terrell marveled at the 3-foot-by-4-foot, 40 pound fragment. It was a classic Haring. Smooth, uninterrupted lines compose the snail figure. Most of the body is a single, spiral line beginning at the shell. A second line makes the head and cute antennas. A third series of strokes forms the face. The bright orange body contrasted boldly with the gray concrete slab.

“I couldn’t believe I was holding in my hands something that was an original art work by one of my artistic heroes for sure,” Terrell said, “and to hold something by someone who was a very strong man and represented an entire generation of gay men who faced the AIDS epidemic.”

Terrell penned a first person story about his discovery that appeared on the Huffington Post website last week.

“I felt like I was touching a piece of my own history,” he said.

Haring’s distinctive drawings took him from a subway artist to the white walls of Soho galleries and beyond. His instantly recognized work showed up on pins, T-shirts, refrigerator magnets and other items sold in his Pop Shop in Soho and Tokyo.

Nowadays, authenticated works fetch between $500,000 and $1 million each.

Auten said he never considered trying to sell his Haring fragment. He didn’t even think it belonged to him. He was just holding onto it.

Terrell affectionately calls the piece “Mr. Snail.” He recently hashed out plans with Auten and Gallentine for preserving and displaying it.

It will hang in a new art gallery in the underground passageway between Hughes Spalding and Grady, where its intended audience — sick kids — will pass by. Gallentine said Children’s is working on building a special case to preserve the fragile piece with hopes of displaying the Haring piece during the coming months.

“Mr. Snail will live at the end of the hallway, where the passageway turns and goes under the streets of Atlanta. Kids will see Mr. Snail get bigger and brighter as they make their way to Grady for treatment, and he’ll be the first person to greet them when they come back to Hughes Spalding,” said Terrell.

“I’m glad he’s made it back home.”