Three tri-town women will be going the distance on Sept. 13 for charity, for their own health and for chocolate.

Grace Knox, 52, Lynn Amicucci, 54, and Marsha Hartley, 60, have signed up to ride 65 miles through Hershey, Pennsylvania and surrounding areas for the Tour de Chocolate Town, with proceeds going to the Children’s Miracle Network.

“We’re hoping at the end we get chocolate. We’re going to be very disappointed if there’s no chocolate,” said Knox.

For Knox, a Mattapoisett resident and owner of DG Service Company, the Tour de Chocolate is another step towards the two-day Pan-Mass Challenge, a fundraiser for the Dana-Farber Cancer Institute. After her husband passed away suddenly from cancer a few years ago, Knox added the challenge to her bucket list.

“I was really going to do it alone,” she said.

But then, Knox and Amicucci discovered they had both recently purchased road bikes. They started riding together and decided they would begin training for the Pan-Mass Challenge.

“I’ve always been involved in sports, yoga, Pilates,” said Amicucci, a Rochester resident and interior designer. But she admitted getting on her new bike was a challenge.

“I could barely ride a mile. This year I started going to the gym more. Now I can’t believe I’ll just say I’m going for a quick twenty-mile ride,” she said. “To me, it’s crazy.”

The pair both take yoga lessons from Marsha Hartley, who owns Studio 105 in Rochester. When they told her about their riding, they found out Hartley had done several long distance rides, including a 100-mile ride in 2007 along Pacific Coast Highway with her daughter and daughter-in-law. The ride was for juvenile diabetes, a disease Hartley’s grandson was diagnosed with before his fourth birthday.

“None of us were bike riders. We all went out and bought bikes and started training,” she said.

Since then, Hartley has done several long charity rides, including a 50-mile ride through the steep inclines of New Hampshire in the driving rain. The Tour de Chocolate ride was something she had planned to do with her niece, Katie Hartley of Clinton, who is an avid cyclist. Hartley invited Knox and Amicucci to join them for the ride.

Hartley said she’s banking on her daily yoga and Pilates classes to get her ready for the ride.

“I just get on the bike and hope,” she said.

Knox and Amicucci, on the other hand, are training in the evenings, with a long 42 to 44-mile ride once a week.

As a lifelong recreational bike rider, Knox said she is comfortable on the road, though her sleek road bike is somewhat different than her cruiser (named Dorothy) with its “Toto basket” in the front and large fake flower on the back.

“Dorothy is very famous but she would never have made the Pan-Mass Challenge,” said Knox.

The women said they’re planning to enjoy the Tour de Chocolate as more of a personal challenge than a race.

“I’m proud of myself because of where I was last year and where I am this year,” said Amicucci.