WATCH: 89-Year-Old Grandmother and Her Grandson Have Visited 29 National Parks Together

Once you have the travel bug, there's no slowing you down. And Joy Ryan is showing no signs of slowing down.

Back in 2015, her grandson, Brad Ryan, took the now 89-year-old grandmother on a road trip to the Great Smoky Mountains National Park after the Ohio native told him, "It’s a shame I didn't get to see more of that in my life—" referring to never having seen mountains or the ocean—"I never had the chance to," she said, per TODAY.

The trip was a hit, and inspired the pair to travel to 21 more national parks in under a month's time. "It's everything you see on the surface: a lot of laughter, a lot of smiles, a lot of breathtaking landscapes. I saw her eyes come alive in a way that she would never be able to articulate with words," Brad Ryan told TODAY. "But on the flip side there were a lot of unanswered questions. So the 28 days were also about having difficult conversations, learning how to forgive each other, and gain more understanding about what went down," Ryan adds, referencing a tough period the relatives endured following his parents' divorce.

Fast forward to 2019, and the duo is on a mission to make it to all 61 national parks. So far, they've visited 29 and you can track their journeys on Instagram @grandmajoysroadtrip. According to their social media account, they plan on hitting the road again in September.

If you're lucky enough to have vacationed with your grandparents, what's the coolest trip you've ever taken with grandma or grandpa along?

Considering a few short years ago Grandma Joy had never traveled much beyond her hometown and now has seen nearly half of our nation's national parks, it's a good reminder that bears repeating: Adventure knows no age limits.