My dad built a Disneyland-inspired theme park in his backyard, just for his grandkids

This story first appeared on Babble and is reprinted with permission.

Most people would say that being a parent is like riding a roller coaster - there's the ups and downs and all-arounds. Well, for my dad, his roller coaster isn't a metaphor; it's a literal one. A physical, adult-sized one. Bolts and all.

And he built it in his own backyard.

But this roller coaster isn't the only thing Steve Dobbs created in that backyard. In fact, it's just the latest addition to a complete Disney-inspired theme park he built for his grandchildren - all five of them, the oldest two of whom are my sons, Zack and Jacob, ages 12 and 15.

Of course, my dad didn't create his Disney-themed backyard overnight; it evolved over time. Its seeds were first planted about eight years ago, when he constructed his very own home-grown version of the Pirates of the Caribbean attraction ride.

It was an instant hit.

(OK, so my kids' expressions would lead you to believe otherwise. But I promise those scowls had nothing to do with their excitement - my dad asked them to "look like pirates" before we snapped this pic!)

For his kid-sized pirate ships, my dad substituted cardboard for wood, marker-sketched drawings for fancy graphics, two spring-loaded ping pong shooters for cannons, imagination for water, and role-playing boys for pirates. After all, a little creativity tossed with some nostalgia and a whole lot of grandfatherly love can go a long way - maybe even beyond the Caribbean.

Eight years and three more Disney-loving grandkids later, and it's finally here: A more, well, expanded theme park, recently completed by my dad and affectionately called "Dobbsland."

For starters, there's the Winfred-the-Poof ride, complete with animated Disney plush characters and voice-over narration (courtesy his son-in-law, Marcus) reading a poem Steve wrote based on a blustery day.

While riding the Madderhorn Roller Coaster, watch out for the animated Yeti inside a painted tarp-covered mountain.

Pretty impressive, huh? The roller coaster itself was made out of wood, and can reach a speed up to 12 miles an hour on a 100-foot long track of PVC plastic pipe.

But if you asked my dad - a retired Boeing aerospace engineer and current engineering college professor - to give you some facts about that roller coaster, he'd proudly explain how he couldn't have done it all alone. It was designed and built with the help of his student team at Cal Poly Pomona.

There's also the Sleeping Princess Castle that delights his two princess granddaughters. It includes animated dolls from Disney's Frozen in a thematic story scene called "Freezing."

And of course, Tiny World provides hours of fun with animated dolls inside donated from my mom's old doll collection she was about to throw out.

Only a 15-minute drive from real-life Disneyland, and nestled in the city of Fullerton, California, Dobbsland might be miniature in size, but it's huge in the hearts of our family and friends. The park itself fits about 50 people and has hosted everything from birthday parties to play dates. But the best part about Dobbsland? Admission is absolutely free.

Still, more than a few times now, people have asked my dad why anyone would spend thousands of hours building such a fanciful place, when the real amusement park is only miles away.

It's always then that my dad says proudly:

"I wanted to show my family, my grandchildren, that anything is possible - even building an adult-sized roller coaster - with curiosity, imagination, vision and, of course, a lot of hard work. And so I created a wonderland specially for them so they can be inspired to always challenge themselves to dream big and then act even bigger."

Life can be an adventure like that.

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