The largest outdoor evergreen maze in the continental United States is now open in Mattituck at Shamrock Christmas Tree Farm on Main Road in Mattituck.

“Everyone here has a corn maze, but nobody else has this!” said Jonathan Shipman, who manages the farm’s pumpkin patch and new evergreen maze. “Our arborvitaes, which are evergreens, tie right in with our Christmas trees.”

And they are towering arborvitaes — 13 1/2 feet high — forming a twisting, turning maze of about 1,000 trees. The maze sits next to the farm’s 20,000 Christmas trees.

It was 2018 when Shipman sat down at his home with a simple piece of graph paper and mapped out the maze.

“Then I bumped it up to scale to fit the property, and I planted the entire field in grass. I used athletic marking tape, the kind you use on a soccer field,” to lay out the zigzagging labyrinth.

In went the coniferous evergreens, which are in the cypress family. Those saplings were just 16 inches tall.

Determined to make the maze accessible to everyone, Shipman made the paths wide enough for people in wheelchairs. He also incorporated a courtyard in the middle of the maze, a space he says is big enough to host a wedding for 120 people.

He declined to ballpark how much the maze cost to build.

“I couldn’t even imagine. I’ve been maintaining it; it gets sheared once a year, and we put in a huge fireplace. That was a big expense. I don’t expect to recoup the cost anytime soon.”

Tickets are $15 per person.

Almost a decade later, equipped with a water supply and 18 electrical outlets, the meandering maze opened Saturday, Oct. 3.

“It makes me so happy to open it because we have maintained it to the highest standard for the public,” Shipman said.

He estimates it would take the average person about 45 minutes to find the exit.

“It’s calm and serene until you encounter a zombie!” he said with a chuckle.

Adding to the North Fork’s long list of autumn activities for visitors, there are 10 Halloween animatronics throughout the maze as part of a scavenger hunt. The creepy characters, including the Brewing Witch, Zombie, Pumpkin Head with Ax and Horrifying Hickory, are dying to spook guests. They jump to life when maze walkers get close to their sensors, their menacing screams, sinister laughter and boos echoing through the thickets. Some have eyes that glow in the dark; others jump out at passersby.

Hedge mazes trace their roots to the elaborate knot gardens of Renaissance Europe. By the 16th century, gardeners were creating labyrinthine designs using low-growing herbs and shrubs, with dwarf boxwood becoming a favored plant because it could be clipped into dense, intricate patterns. Surviving illustrations of European garden knots date to the 15th century, and hedge and garden mazes became increasingly popular in Europe in the centuries that followed.

Probably just like our ancestors, today’s maze-goers at Shamrock were challenged by how to navigate the walking puzzle to the end.

Through the thick, soaring walls of fluffy green foliage came the voices of those trekking down the paths.

“I’m lost!”

“I think I’ve gone this way before!”

And to make it even more challenging, they encounter the labyrinth’s 19 dead ends.

With maps in hand and ready for the unusual adventure, mother and daughter Annette and Michelle Torres of Massapequa Park said they came out east just for this.

“I’m lost already!” Annette said, laughing.

“It’s so cool,” Michelle said. “I’ve never seen this before. I’ve gone to corn mazes and got lost, too.”

Wondering whether to go left or right — and whether either direction would get him any closer to the courtyard in the middle — Alec Arza of Ronkonkoma was walking with his parents, Miriam and Mike.

“It’s actually pretty cool. It’s fun trying to find all these characters in the maze,” Alec said.

His dad, Mike, figured it might be more advantageous if they went in separate directions.

“It’s a lot easier than I thought,” he said.

His wife, Miriam, joked, “It’s kind of scary, like ‘The Shining!’”

For 12-year-old Dean Celatka of Laurel, who made his way through the maze, it was very “Halloweeny.”

“It’s cool and spooky,” he said.

And there are plans to extend the season for the maze. Shipman is considering transforming it in time for the holidays, replacing the Halloween characters with displays inspired by the holiday song “The Twelve Days of Christmas.”