It can be hard to find inner peace in the middle of a bustling city.

It’s not too difficult for Greta Lea-Plaza, though, who holds free yoga classes on the Waltham Common Saturday mornings in the summer.

“It was just an idea to offer some classes outside since it was the summertime,” said Lea-Plaza, who is originally from Florida.

She’s been practicing yoga for the past 15 years and moved to Waltham last year to work at the Cambridge Institute of International Education on Main Street, where she hires and trains ESL teachers.

Lea-Plaza decided she wanted to teach yoga after practicing it for nearly half her life. She completed her 200-hour teaching certification with Inner Strength Studios last December and has been teaching at the Watertown studio ever since.

“A lot of working moms at my regular job said they couldn’t afford to go to the studio, so I wanted to offer some free classes,” Lea-Plaza said.

She went to city hall to see if there was any space available on the Common, and most Saturdays since mid-June Lea-Plaza has been teaching yoga in the early summer sun at 8:30 a.m.

All skill levels are welcome at the morning sessions and the feedback from the handful of attendees so far has been mostly positive.

“At the beginning it was pretty much just friends and my husband,” Lea-Plaza said. “The goal is to get more people to come the last few weeks.”

All are free to join Lea-Plaza on Saturday, Aug. 6, 13, and 20 near the gazebo on the Waltham Common from 8:30 a.m. to 9:30 a.m.