FRESNO – Sartre got it wrong. Hell is not "other people." Hell is Fresno in the summer. Hell is opening your car door at the prick of noon on strip-mall-strewn Shaw Avenue and getting a face full of oppressive heat. Hell is feeling the rivulets of sweat trickle down your back as heat-wave shimmers make the asphalt appear liquefied.

Yet, your express purpose for coming to this baking Central Valley metropolis is to escape the merciless heat, at least temporarily.

Are you mad, or is it just heatstroke that has caused this cognitive dissonance? Fresno seemingly is the last place, other than the surface of the sun, to go to avoid the summer swelter. Head to high-altitude hills or coastal climes, anywhere but to this bubbling crock pot of calefaction.

But then, you make a right turn on Shaw just after the Carl's Jr. and follow a tree-canopied path down past Roman archways, down farther to a cool, blessedly cool, underground sanctuary, down to the architectural and horticultural wonder that is the Forestiere Underground Gardens.

You would gladly pay the $14 admission price simply to linger in the lobby, maybe 25 to 30 degrees cooler than the near-lava Fresnan mantle above ground. But there's much to see and admire during the 45-minute tour of the 10-acre subterranean oasis built by Sicilian immigrant Baldassare Forestiere more than a century ago.

The only bad part: The tour lasts only 45 minutes, meaning the kiln that is your car awaits.

Whereas many Fresnans flee the Valley like refugees each summer, beach-bound or over yonder to Yosemite, some have lived here for decades and never set foot in the city's most notable roadside attraction.

"I live a mile away and have never been here," said Connie Seay, who brought her 4-year-old niece, Makenzie Wilcox. "We talk about it at my workplace all the time. 'Wonder what the underground is like?' It's right here and you know you can go at any time, so you don't. You know?"

In a way, summer is the best time to go underground. Visitors can get a full appreciation for the inspiration and desperation Forestiere must have experienced when he started digging to find relief from temperatures that must've seemed biblical.

What began in 1906 with the modest goal of sculpting a couple of cellars later blossomed into a lifelong endeavor that is an impressive display either of single-mindedness or of obsessive mania. That's because Forestiere just kept digging. Digging for the next 40 years.

The result is a singular space, a labyrinth of nooks and niches, full bedrooms and kitchens, courtyards and chapels, a wine cellar and underground citrus orchards.

As docent Latieshka Simmons wryly observed to a group of 15 sun-fleeing visitors, "After he built it, Forestiere couldn't understand why all people from Fresno didn't live underground. What is wrong with these people? It's so much cooler down here."

Until embarking on his quixotic downward dig, Forestiere was an aspiring citrus farmer down on his luck. He emigrated to the United States in 1901 and helped build the subway system in Boston. California and fruit trees beckoned, and Forestiere made a good choice for a relocation spot – Orange County.

"He loved it down there," Simmons said. "The only problem was, the cost of living was a little pricey. He couldn't afford the land. Then he heard about the Central Valley. The land was cheaper."

For good reason. When Forestiere first put spade to earth to plant trees in 1905, he soon hit solid hardpan. It can range from a foot to 5 feet under the initial topsoil, rendering the land useless. Good luck trying to get anything to grow here.

"In the summer, he gets another surprise." Simmons said. "It gets hot, 115 degrees maybe, every single day. This is before air conditioning, so Forestiere is hot and miserable. So he starts brainstorming about how to get cooler."

After stewing in his wooden shack, oppressed by the heat and his situation, Forestiere hit upon a plan for his 80 acres.

"He knew from his experience building subways that it's cooler underground," she said. "He started digging out cellars. He moved his cot down there. Then his stove. Then he just moved in."

And kept digging, hand- excavating his own Middle Earth with only a pickax, a shovel and steely resolve.

Soon, Forestiere moved underground, carving out rooms and alcoves, boring funnel-shaped skylights to improve ventilation and visibility, adding Mediterranean flourishes.

Then came the planting. If Forestiere could not sow seeds for an orchard above ground, he knew the soil was rich enough 20 feet under to support growth. He started with ferns and herbs, which thrived, adding all manner of fruit trees (orange, grapefruit, lemon and grafted hybrids that resulted in one tree featuring seven types of fruit), grapevines, carob and date trees and roses.

What started as a whim became a consuming passion. Over time, Forestiere built 50 rooms, a wine cellar, a snaking tunnel made for automobiles, even a pond for fish to frolic (before they became dinner). Period photos of Forestiere show a man of lean and wiry build, with a furrowed brow and sculpted cheekbones and a winsome countenance. The modifier that pops into your head: "long-suffering."

At this point, a woman on the tour asked what everyone had been thinking: Did Forestiere ever marry?

Simmons smiled, seemingly prepared with the official Underground Gardens answer.

"No, never got married or had kids," she said. "People at the time were curious about Baldassare, and the Fresno Bee people came out to write about him and they were expecting a (she whistles and circles a finger around her head) crazy man. But he actually was a very brilliant man, a very friendly guy."

He built those 50 rooms, she said, in hopes of opening a resort for other heat-oppressed Fresnans. As the newspaper account quoted him as a saying, "The visions in my mind overwhelm me."

Alas, the resort never came to pass. He worked on expanding the underground manse until 1946, when he died of pneumonia after undergoing a hernia operation. He was 67.

Simmons repeatedly made the point that Forestiere was "not a hermit or recluse," despite his cave-dwelling penchant. When she shows the tourists the chapel, complete with a mission bell at ground level, where Forestiere would worship alone at day's end, some wise guy in the group muttered, "Yeah, and he wasn't a loner?"

"No, he really wasn't," Simmons said, voice rising in emphasis. "It's not like he was down here working and digging, 24-7. He loved people, built this for people to come visit. He was friends with a lot of the Japanese in Fresno. They shared that common immigrant bond and he'd bring them down here. His brother Giuseppe, and (Giuseppe's) children would come down, too. So, again, he wasn't a recluse. I must reiterate that."

The Forestiere family still owns the gardens and they make sure Forestiere's character is not besmirched.

"According to Ric Forestiere (84, the property's owner and Forestiere's nephew), Forestiere did have a couple of lady friends who'd visit him often down here," Simmons said.

Even if Forestiere was not a recluse, it seems fair to say he, like many with an artistic temperament, had his quirks.

In one of his two bedrooms (one for summer, designed to keep heat out; one for winter, to keep heat in), Forestiere built a "peep hole" in order to espy visitors at his door. It consisted of a snaking tube running from his fireplace to outside the door, at ankle-level. If you wanted entrance into this sanctum, you had better pay attention to your footwear.

"He could look and figure out who you were by your shoes," Simmons said. "If you knocked at the door, if he knew your shoes, you could come in. If he didn't recognize your shoes, then he'd just let you stand there and knock.

"I imagine some of his friends saying, 'Don't shoot, Baldassare, I've got new shoes on ...' "

What no one questioned was his dazzling engineering achievement using only hand tools and, later, a Fresno scraper, pulled by his beloved horses Dolly and Molly, to craft canals.

When it came to sustainable living, Forestiere was nearly a century ahead of his time. Self-taught, he not only devised natural air-conditioning of 70 on the second floor and low 60s on the third, but he funneled rainwater in to irrigate the subterranean trees and even fashioned solar-powered hot water for his bathtub.

"He kept a metal tank upstairs at ground level," Simmons said. "The sun would heat the water all day while he was working. At night, he'd drain it into his bath. How cool is that?"

Cool is several respects, actually. And the group, which was in no hurry to leave, seemed suitably impressed.

"He must've been a neat guy," said Marian Smith, visiting with her husband, John, from nearby Kingsburg. "At first, I thought he must've been a nerd. But he wasn't."

"I'd actually enjoy living in these temperatures all the time," John added.

True. Think what you want about Forestiere – eccentric or cuckoo – but grant him this: He was smart enough to escape the hellish Fresno heat.

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