ST. PETERSBURG — When demolition crews ripped down the grillwork encasing the old Pheil Hotel this week, they uncovered more than the building's original brick facade.

They revealed a secret hidden in the heart of the city:

Letters a story high that spelled out "AV8R" across the eighth story of the 11-story building.

It may very well be the largest "tag" — a graffiti artist's personal signature — ever spotted in the city.

"Good Lord," said St. Petersburg police Detective Ron Krickler as he looked up at the side of the building facing Central Avenue on Tuesday morning.

It's Krickler's job to corral the city's graffiti artists. And this particular tag was familiar to him.

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It was no easy feat.

The artist, the detective surmised, climbed up the grates that gave the Pheil Hotel its nickname as the "cheese-grater" building. Balanced precariously between the sheets of metal and the brick wall, the artist likely used a large roller to paint the thick black letters.

There's no way to tell when it was done, either. The paint didn't look fresh to Krickler. It was maybe a year old, he guessed.

Graffiti artists call them "heaven spots." That's when they create works of art in hard-to-reach places — even dangerous ones — to prove their mettle, to make a name for themselves.

"Graffiti writers are, by nature, a resourceful group," said Gregory Snyder, a sociologist and author who has studied the craft. "In addition to being amazing artists, they're also risk-taking, athletic superheroes."

Snyder, a professor at Baruch College in New York City, said whoever was behind that monster tag likely took risks "where one wrong move could lead to a catastrophic circumstance."

But why would anyone risk their life for this particular art?

The goal of most artists is notoriety, Snyder said. He also doubts that it was a coincidence that the tag was left so close to the Tampa Bay Times' newsroom across the street, on First Avenue S.

Artists want attention. They want to make a statement. And that might be worth the risk.

"It's an act of creativity," Snyder said, "and an act of bravery."

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Jared "Thirst" Hernandez was arrested by St. Petersburg police on Feb. 11, 2015.

A video surveillance camera caught him spray-painting "AV8R" outside the Lucky Dill Deli on 277 Central Ave., according to a police report, a short walk from the "cheese-grater" building.

Hernandez faced six counts of criminal mischief for painting tags such as "AV8R," "AV8ER" and "AVY8ER" across the city. The police report said "this graffiti tag is a personal identifier to him."

His attorney at the time, Richard McKyton, said most of the former charges were dropped for lack of evidence. Hernandez did plead no contest to one count and paid $575 in a fines and fees.

Hernandez could not be reached for comment this week. He did not return messages left via social media.

Based on his experience with graffiti artists, Krickler said he doubts Hernandez would paint his tag again after his 2015 arrest. He's too well known to officers, and they know his favorite tagging spots.

The police are not investigating the giant tag on the Pheil Hotel. The detective isn't even sure there would be enough evidence to bring charges. The tag is old, and there are no witnesses or video footage.

There may not even be a victim. The building's owners are tearing it down to make way for a soaring tower, possibly for condominiums.

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Hernandez, now 29, is known for a lot more than tagging these days.

According to stpetemuraltour.com, he painted some of the city's first murals. He painted a scene of outer space in an alleyway and another mural of the 1990s TV character Steve Urkel eating ice cream on the side of a convenience store — works of art he signs as "Thirst."

In a way, the giant "AV8R" scrawled across the "cheese-grater" is a reminder that the city's popular mural scene was started, in part, by the graffiti artists of the past.

That goes to the heart of the tension inherent in graffiti and other forms of street art, said Pitzer College professor Susan Phillips.

Some see it as vandalism. Others as art. But not much separates the two.

The Pheil Hotel tagger "is using the building to make this monumental piece that's his (or her) name," she said. "It's really beautiful, actually."

It certainly gave the detective who chases down the city's graffiti artists something to think about.

"That was underneath," Krickler said, "just waiting to be uncovered."

Contact Sara DiNatale at sdinatale@tampabay.com. Follow @sara_dinatale.