My son Japhy, 5, still spontaneously falls off his chair from time to time, and is shaky on his pedal bike, but at Diggerland USA, a construction-themed amusement park in southern New Jersey, we have given him control of a 7,092-pound JCB excavator. He is sitting high in the cab on his father’s lap, moving the enormous boom arm of the digger to scoop earth and dump it out.

This was the founding ideal of Diggerland: For families to experience the thrill of operating real construction machinery.

The park was opened in 2014 by Ilya and Yan Girlya, Moldovan American brothers who worked for their father’s construction firm and opened Sahara Sam’s Oasis Indoor & Outdoor Water Park in the 2000s in a lot adjoining what became Diggerland. At Diggerland, the owners have worked with construction equipment manufacturers like JCB and Ventrac to modify dozens of models for safe use by children starting at 36 inches tall (some rides require children to be 48 inches tall, but all children can be lap passengers).

The engines have an auto shut-off, the cabs have rollover protection, the machines’ tracks are fixed in place, and the turn adjustment on the diggers is limited, so the pint-size operators can’t drive off or go rogue. It is a playground of yellow and black where dumper trucks, tractors, backhoes, rollers and, of course, diggers crawl around set courses or paw through their designated spot in the ground. By design, the park looks half-finished, a 21-acre arena of concrete bollards, storm fencing and site offices selling neon pink, yellow or orange safety vests, matching construction helmets and hot dogs.

There are also rides grafted together from various hydraulics, like the Dig-a-Round, a carousel of dangling yellow claws; the Sky Shuttle, in which guests are lifted 50 feet toward the sun in seats welded onto the scoop of a telehandler (a giant version of a forklift); and a ropes course fashioned to look like high-rise scaffolding. At the rear of the park, the Water Main offers a wave pool and various slides and splash pads in homage to plumbing infrastructure. For the Girlya brothers, the park embodies the possibility their parents saw leaving the U.S.S.R. in 1979 to “create a life for the family with the freedom to be anything you want and enjoy all the opportunities America can offer without any fear of persecution,” said Ilya Girlya in an email.

The appeal for children is obvious. Like Tony Stark inside his Iron Man suit, they gain superpowers when they grip their hands on the levers, their minds assuming control of a gigantic exoskeleton. “All the tools and engines on earth are only extensions of man’s limbs and senses,” wrote Ralph Waldo Emerson, perhaps in anticipation of children’s fondness for driving cars.

Entering the park on a recent Sunday, I saw a staff member working vigorously to correct the wild steering of a child navigating a Roxor off-road vehicle, which unlike the diggers, operates on an open course. Elsewhere, guests strapped into chairs in the scoop of a JCB JS200 digger spin around in a blur of centrifugal force known as the Spin Dizzy. Throughout the day, a call echoes over the P.A. system: “Caaaaan youuuu dig it?”

My daughter Scout, who’s 7, takes a ride on the Elevation Station, a scissor lift, and then Japhy hops into a small barrel car being towed by a Ventrac tractor — “the one with sunglasses and a smiley face,” recalls Japhy. Later, they each take a turn steering a 1,310-pound diesel Terex Dumper Truck around a course with my foot on the accelerator pedal. Scout adds to the thrill of commanding this beast by taking her hands off the wheel and letting it “drive itself” toward the barriers, a reminder of why we haven’t let children drive the open roads since the early 1900s.

We make our way to the slightly finicky Mini Diggers, each of which weighs as much as a newborn humpback whale, and which have been modified so that the operator uses the arm to knock down bowling pins or to hook foam ducks from a small pond. By the time we came close to knocking down a pin, the machine would shut off. Luckily no major infrastructure project was reliant on our skills. In the line, a father gives me a conspiratorial look. “Wonder if they ever open the park just for adults,” he asks. (No, but right next door, Diggerland XL provides an adults-only experience driving full-size equipment through a course, advised by a staff member via two-way radio.)

There are also coin-operated Micro Diggers, while the JCB 8030 “Big Diggers” are the largest of the excavators.