It is an emerald hidden in plain sight. A gem of a green tucked away across the loop from McCoy Pavilion but obvious to those who know of the Honolulu Lawn Bowls Club.

Constructed by Australian servicemen stationed in Honolulu in the mid-1930s and dedicated by Lester

McCoy, Honolulu’s first parks commissioner, the green at Ala Moana Park has been home to hundreds of ex-pats and the curious who understand the nuances of a sport traced back to the 12th century. The Honolulu Lawn Bowls Club was officially formed in 1955 and is under the aegis of the City and County of Honolulu.

“I had never played the sport until I was living in Australia in 1995,” HLBC president Mark Berwick said. “I moved back to Hawaii but was not aware that there was bowls here until 2006. I bowled sporadically and then joined full-time in 2009.

“What I like is meeting people from all walks of life. You get a good mix of people and it’s a relaxed, social atmosphere. And it is very inclusive. Everyone can participate, whatever age and whatever physical ability.”

The club hosts free lessons for those interested in learning the sport. Or for those who just happen by, as in the case of Mary and Glenn Sears, who were riding their bikes through Ala Moana Park earlier this summer.

“We saw the club and thought it might be something fun to do,” said Mary Sears, who joined with her husband two weeks ago. “We had moved back to Hawaii after 40 years on the mainland and we were looking to continue doing things outdoors.

“The members were very nice, very accommodating. It’s easy to learn but hard to excel.”

The sport is played on a rectangular leveled and manicured grass surface known as a bowling green. It is divided into parallel playing strips called rinks, where the object is to roll slightly asymmetric bowls — also known as balls or jacks — so that they stop close to a smaller jack.

To the uneducated, it seems a combination of 10-pin bowling, bocce, croquet and curling.

“The important thing is the concentration,” said 80-year-old John Gilbert, HLBC director and the senior club member. “It’s a game of considerable strategy. You can play for years and years, but you never master the game completely.”

Gilbert, a self-described seasoned bowler originally from Australia, has played on greens around the globe from Paris to London to Honolulu. He has seen the popularity of lawn bowls fluctuate over the years, but particularly has noticed how the dress code has been relaxed.

Proper bowlers wear white as a matter of etiquette — much like the old standards of tennis. Bowling shoes are flat, so as not to rip or tear the green.

Men wear trousers or shorts, and women wear trousers, shorts or skirts at knee-length. Both sexes usually wear white polos.

“It’s not as strict now,” Gilbert said. “There was a time when they would measure the hem-lengths of women’s skirts. Now, I’ve seen games where they play in bare feet.”

Berwick said he didn’t want the perceived dress code to be a deterrent for those interested. Besides the free lessons, the club also offers free use of equipment.

The cost of membership starts at $7 for one day. The club also has lockers and a kitchen for members’ use.

“You can choose fees that are daily, weekly, monthly and annual,” Berwick said. “You can pay for a couple of times to decide whether it’s for you or not. We provide free lessons for beginners and we’ve had corporate days where businesses will come in for games and socialize. And the club has barbecues and evenings with live music. I’m all about creating a fun, social atmosphere where you have a great place to hang out with a nice group of people.”

The club bowls year-round, with weekday hours that vary and standing play at 10 a.m. Saturdays.