TAMPA — A real estate listing touts the features of a 2,068-square-foot home for sale on North 12th Street: Three bedrooms, two bathrooms, a basement, a courtyard with Mediterranean-style shed, and beneath the shed, "its own bunker."

Welcome to Ybor City, where you find history on every corner, and sometimes — thanks to the Latin district's Mafia past — underneath them.

The home, built in the 1920s, was owned in the 1930s and 1940s by rum- and numbers-runner Jimmy Lumia. The 20-by-10-foot bunker runs as deep as 12 feet and likely is where Lumia hid his wares. The home's basement even appears to have a walled-off entrance of some kind.

"From what I understand, that led to a tunnel that led to another house," said William Crescenzo, representative for the home's owner Stephen Hickey.

Beneath Ybor City's business district lie at least three brick tunnels that have inspired a host of theories from historians — highways for the trafficking of moonshine, or numbers, or people, or maybe all three.

If you own a home in Ybor City, you never know what you'll find.

The Lumia residence is in a leafy neighborhood of bungalows and older homes about a third of a mile north of Interstate 4. The area, known as V.M. Ybor, was divided from the business district with the construction of the interstate.

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Lumia worked to keep up the appearance he was the law-abiding owner of an oil company and gas stations, said mob historian Scott Deitche. But by the late 1930s, as his power grew, Lumia could no longer hide his mafia connections.

"He was considered a figure in Tampa's gambling scene and considered a key part of the Mafia power structure," Deitche said. "The FBI called him a significant player in organized crime. So, one could surmise he could use somewhere to store stuff where people could not find it."

An underground bunker with no lights or windows might also serve to intimidate enemies, Deitche said.

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Attorney Crescenzo said rumors of a bunker spurred the excavation of the shed's concrete floor about four years ago.

"There it was, with 12-inch-thick concrete walls," he said.

Kelly Grimsdale, who owned the home in the early 2000s, had no idea she was living on top of a hidden bunker. Still, as a longtime resident of V.M. Ybor, she quickly understood.

"There are secrets everywhere."

Grimsdale talked about a two-story bungalow on the corner of 13th Street and 20th Avenue that features a wooden staircase behind a second-story bedroom cabinet. It leads to a secret attic, she said — maybe where moonshine was kept.

In the 1930s, federal investigators uncovered a bunker at 1014 10th Ave, said Del Acosta, an architectural historian.

"People stored their liquor in underground vaults," he said.

Acosta is one of the few people who have stepped inside one of Ybor City's infamous tunnels.

"I am 5-foot-8 and I could walk in it."

The system he explored lay underneath the site of the Blue Ribbon Grocery Store, at 14th Street and Seventh Avenue. Where the tunnel once led remains unclear. By the time he entered, it had been sealed off just 15 feet inside.

A fire in 2000 destroyed Blue Ribbon and any trace of its tunnel.

Some people believed the underground path led across Seventh Avenue to what used to be Las Novedades restaurant, where there appears to have been illegal gambling, said mob historian Deitche. The tunnel could have offered an escape route during police raids.

Another tunnel may have connected the Ybor Factory Building at 1901 N. 13th St., Tampa's first cigar factory and now a Church of Scientology site, with the El Pasaje building at 1320 E 9th Ave., later the headquarters of Radiant Oil.

"Stories are that El Pasaje had a brothel," Deitche said. "Men could go in and out without being seen by using the tunnel."

While working on the TECO Line Streetcar System in the early 2000s, crews uncovered a tunnel outside Curts Gaines Hall Jones Architects at 12th Street and Sixth Avenue. It was large enough to walk through, president Gerry Curts said, and ran about 250 feet toward the Ybor Channel before splitting in two directions.

If one of those paths stretched to the water, illicit cargo might have been unloaded from boats and carried into the city, Curts theorized.

Historian Gary Mormino said "old timers" told him the tunnels were used to traffic Chinese immigrants during a period from the 1880s through the 1920s when laws made it almost impossible for Asians to immigrate to the United States.

Added Mormino, "I am dubious as to whether we will ever arrive at the truth."

The basement of the architecture firm has two sealed tunnel entrances but construction in the area over the years has yet to reveal where they might have led.

The building housed the bottling center for the neighboring Florida Brewing Co. while it was in business. During Prohibition, the brewery stayed open making medicinal alcohol and might have used the tunnels to smuggle booze to gangsters, said Deitche, the mob historian.

There's also a more prosaic theory behind the creation of the tunnels, said Rodney Kite-Powell, curator of the Tampa Bay History Center. The workmanship and expenditures involved suggest a public works project, Kite-Powell said — maybe drainage.

They might have been re-purposed later, he said — maybe even for legitimate business reasons.

"Everything in Ybor back then was done in cash," Kite-Powell said. "So, I can see moving cash around through those tunnels as a way to not get robbed."

If the Lumia home had a tunnel, Kite-Powell said, escape or smuggling is the only purpose he can imagine for it.

"Someone like that has the wherewithal and need."

A portion of one basement wall of the home has a different shade of concrete than the rest of the room. Behind that spot, Crescenzo said, is where the tunnel lies.

He and homeowner Hickey considered cracking it open, as they did the shed floor. But they decided it wouldn't be worth the damage it would cause.

"We are curious," Crescenzo said. "But it will be up to the next owner."

The home's distinctive design features pointed arches and a second-story veranda. It has the all-wood floors and stairways common to its era and has been restored with modern tile, cabinets and appliances. The asking price is $299,000.

As for Lumia, he met his end in 1950 as he sat in his car outside his oil company near the Port of Tampa.

A truck drove by and someone inside fired a shotgun blast, hitting him in the head, Deitche said.

The hit came as the notorious Santo Trafficante Jr. was consolidating power on his rise to become Tampa's organized crime kingpin.

"Of course," Deitche, "as is always the case, the murder remains unsolved. It's a mystery."

Contact Paul Guzzo at pguzzo@tampabay.com. Follow @PGuzzoTimes.