Every Monday, Wednesday and Friday, a group gathers at Diamond Head Tennis Court to play a sport you might not have heard of.
The game is called pickleball and it's taken Hawaii by storm. It incorporates elements from ping pong, badminton and tennis, and its popularity has exploded in the islands over the past two years.
"Since starting to play pickleball, I have met people from all over the world," said resident Theresa Mitchell.
Mitchell picked up the sport three years ago. She's one of an estimated 2.5 million people who play the game nationwide.
"I'd been looking for a new sport. It's also a game that's really easy to learn. Basically after five minutes of instruction you could be playing pickleball," said Mitchell.
But the biggest draw for many athletes is that it's easy on your body.
Sixty-nine year-old Rudy Lopez had to stop playing tennis because of his knees. He says pickleball is a good alternative.
"The court is smaller. Like only 20 feet wide and 44 feet long so not so much running. It's a very friendly sport. Body-friendly and social-friendly," said Lopez.
Getting started is easy. There are 10 pickleball ambassadors on Oahu who will teach you the game. If you don't have a paddle you can borrow one.
"Anyone can come, It's free. It's under the department of parks and recreation," said Annette Cottle, pickleball ambassador.
Since the start of 2015, the city has lined 23 courts at 15 different parks. Cottle believes more would be good for tourism.
"We would love to have a dedicated pickleball site so we could go bid on national tournaments," she said.
Mitchell says playing the game is a bright spot in her day.
"When I first started playing it someone told me you're going to find this addicting. And it's true if I don't get my pickleball games in almost everyday I'm like what am I going to do," said Mitchell.
If you'd like to learn how to pla, head down to Diamond Head Tennis court at 8 a.m. on Sunday for a demonstration.