Incredible Grandpa Builds Backyard Disneyland for His Grandkids (VIDEO)

When your grandfather spent decades as a successful aerospace engineer, there are a couple of ways his golden years can go. He could take up golf and master the physical trajectories of golf balls and 8-irons until he develops an acceptable handicap OR he could build a mind-blowing miniature version of Disneyland in his backyard for the exclusive enjoyment of his grandchildren and their friends.

Luckily for his grandkids, Steve Dobbs of Fullerton, California, falls into the tiny latter category.

Knowing his kids and grandchildren love Disneyland, and by his own admission, wanting to "give them a reason to come over to my house to spend time with me,” Dobbs began by building an amazing replica of "It's a Small World" a few years back. Everyone loved it - but as the kids got older, Dobbs knew he would need to expand the "park" to included more mature attractions.

Over the years, Dobbs would add a series of rides and attraction - each lovingly crafted to speak to the things his grandchildren loved at that time. But the best was yet come...

A professor at California State Polytechnic University, Dobbs enlisted the help of students to create his masterpiece: a fully-functioning roller coaster in the center of the yard. (Yes, you read that correctly)

The family named it "Dobbsland" and to date it has cost Steve almost $7,000 to build. But the money's not really important to him. "It's an old man's hobby," the engineer said recently.

And while admission is FREE, the memories it provides Dobbs' family are priceless.