Brad Ryan and his grandmother Joy Ryan set out on a journey to visit all 63 national parks seven and a half years ago. This week they completed their goal when they arrived at the National Park of American Samoa.

"The National Park of American Samoa is the only U.S. national park south of the equator and our most remote park," Ryan posted on the Grandma Joy's Road Trip Instagram page created to document their travels. "It was a long road to get here, but we couldn't have chosen a more epic place to conclude this epic chapter of Grandma Joy's Road Trip!"

The two received certificates and a number of other gifts from the National Park Service, commemorating their 63-national park achievement.

"We defied erroneous assumptions about the limitations of aging. We defied financial and logistical constraints," said Brad Ryan, who is 41, noting that his 93-year-old grandmother made history as the oldest living person to visit every US National Park.

"Seven and a half years ago Grandma Joy and Brad Ryan set out on a journey to visit all 63 National Parks," National Park of American Samoa said in a post on Tuesday. "For them, however, this was not simply a checklist journey, but one of reconciliation and healing. Today, we were honored to host them as they arrived at their 63rd park and accomplished their goal. Their story is amazing and we are grateful to be part of it."

The duo's journey began after Ryan's grandmother, a resident of Duncan Falls, Ohio, told him she regretted how few trips she had taken during her life, as CNN previously reported.

First he took her to the Great Smoky Mountains National Park, then he started a GoFundMe page to raise money for the other trips.