Competitive indoor axe-throwing, the latest form of inventive leisure, is done with 14-inch axes. And beer. (Kirby Sybert for Urban Axes)

— Competitive indoor axe-throwing is like darts — “but bigger and more satisfying,” declares the Urban Axes website. Also, with a potentially deadly tool and a 12-point liability waiver.

Axe-throwing has officially arrived in the United States. Specifically, in a former textile mill in Philadelphia’s Kensington area, a gritty neighborhood quickly gentrifying with condos, cafes and hipsters. Another, unaffiliated hatchet-hurling venue, Bad Axe Throwing, also recently opened in Chicago.

“It’s not just come and throw an axe. It’s a structured game,” says Stuart Jones, one of Urban Axes’ four partners, who spent part of a recent night, power drill in hand, replacing shredded target boards. “It’s this constant quest for mastery. It’s mentally challenging as well.” Although, he concedes, “it’s not hugely challenging physically.”

Which would explain the beer.

Axe-throwing is played with 1.5-pound, 14-inch axes and is often enhanced by multiple tallboys (you must be 21 to play). Urban Axes is a BYOB venue offering a quartet of kitchen-size refrigerators that on this night are fully stocked with players’ craft and down-market brews. (Wine and food are also welcome.)

The game is the latest entry in inventive leisure, a low-cost activity that provides community, novelty and the newest twist on a party when paintball and painting pottery have become been-there, done-that.

His buddies have surprised Drexel University biology professor and impending bridegroom Kevin Smith with a bachelor party at Urban Axes involving two cases of beer and 2½ hours of axe-throwing at $35 a person. “Better than bowling,” is the judgment of Dan Corrigan, who helped organize the event.

Axe-throwing, which is done in groups of eight or more, or in league play, with 30 competitors who register online. Two players stand in adjacent lanes, taking turns tossing axes at a target 14 feet away. In eight-week league play, competitors play round robin, a computer program assigning the pairings.

And whence did competitive indoor axe-throwing come? You can blame Canada for this, along with a religious devotion to hockey, odd-shaped bacon and an embarrassment of photogenic Justins (Trudeau, Bieber) and Ryans (Gosling, Reynolds).

A decade ago, Matt Wilson was a bartender with an axe. He was having fun, throwing it at a wooden target in his Toronto back yard. Parties, crowds ensued. His dream was to remain a bartender, possibly graduate to bar manager. He had no plans to become an axe magnate, let alone the commissioner of Canada’s National Axe Throwing Federation. (Although, with the inclusion of Urban Axes, it is now technically continental.)

“It’s the entrepreneurial spirit, not the paycheck,” he says by phone from Toronto of the commissioner gig. Good thing, given that unlike the NFL’s Roger Goodell, with his $34.1 million annual compensation, he draws no salary.

Five years ago, Wilson moved the game indoors and opened his first venue. Today, the Backyard Axe Throwing League (BATL) has eight locations in Canada, a ninth set to open in November , and 150 employees.

There are 1,500 league players — that is not a typo — in the province of Ontario alone.

BATL’s mission: “To show people the power of being good to each other, using the axe as a tool to build community inspired by our backyard roots.”

The Backyard Axe Throwing League hosts a skills competition every summer for league members at its home base in Toronto. (The Backyard Axe Throwing League)

At Urban Axes, the decor is steampunk meets Home Depot. Queen wails on the sound system. The aroma? Woody with a top note of takeout.

“I like the whole underground-warehouse, Fight Club aesthetic,” says league member Freddie Patane, who works in video production. Players can purchase axes for $20. Personalization is encouraged. Patane plans to make his own.

On the Thursday league’s inaugural night, many of the players, about 40 percent of them women, are bewildered about basic rules. People have invested $120 for two months of play for a game they barely understand and even fewer have played. (The 16-lane venue offers introductory one-hour lessons for $20.)

How many throws per game, and games per match? (Five, three.) What is a clutch? (One of two smaller targets above the bull’s eye for an extra seven points, but only at specific moments of play.) In league competition, how do you determine which lane to play? Rock Paper Scissors. We are not making this up. A perfect match score? 81. Most Thursday night league members initially scored about 32.

One attraction of competitive axe-throwing: a level hurling field. Most likely, you will stink in the beginning. Later, you will improve.

Or, in some cases, possibly not.

Patane dominated in his first match, wiped out in the second. Size does not matter. Burly lumberjack-like competitors rack up zeros. Tiny players score multiple bull’s eyes.

Kyle Brzezynski is one of three “axeperts” assisting league players and keeping score. “I heard about this and thought, ‘Oh, God, I would love to work there.’ Plus my background is perfect.” Indeed. He studied Viking history in graduate school.

Axe-throwing is about form, technique and muscle memory, not strength. In that regard, if nothing else, it’s a lot like golf.

When tossed correctly, the axe spins in full rotations, registering in the pine target with a comforting thwack. Tossed wrong, not that we know from experience, the metal clanks against the wall and the wooden floor, sometimes boomeranging close to a competitor’s feet. Ergo, the requirement of closed-toe shoes.

Understandably, landing insurance proved a, ahem, pain in the axe.

“We called a ridiculous number of insurance companies and brokers, like 20,” Jones says. The partners finally secured an agent willing “to do a leap of faith,” he says. The result is a waiver that includes provisions such as:

No. 2: I acknowledge and understand that I will be voluntarily engaging in activities that involve axes, which may result in the risk of serious injury, scarring, loss of an important bodily function, permanent disability and death.

Competitors tap axes to start a game. (Kirby Sybert for Urban Axes/ )

Why create indoor venues for throwing axes, an activity you can pursue for free outdoors at home or in the woods? “Leisure is our free-est institution,” says Robert Stebbins, a retired University of Calgary professor who has studied leisure for four decades. “Family and work don’t give us much space for change. With leisure, it can be just as individualized as it can get, or it can catch on and be very social at a certain level.”

That’s how Frisbee, once a picnic activity, ultimately became Ultimate Frisbee, with rules and national and international championships.

Drexel prof Smith, for one, is smitten with axe-throwing and plans to return with his new bride. Two more leagues are scheduled to launch next month. In the next year, Jones and his partners hope to expand axe-throwing to another city on the East Coast, possibly Washington, New York or Boston. (Bad Axe aims to open 20 locations in the United States in the next few years.)

“Axe-throwing is a vehicle to bring people together,” Jones says. “The axe is just a medium to get 30 people to come together and share. The axe is the great equalizer.”