Suspension bridges. Aerial walkways. Rivers and rain forests bordered by a 2,500-foot-high mountain range.

The setting for Outfitters Kauai’s Zipline Trek Nui Nui Loa seems like it was pulled from "Swiss Family Robinson"; it’s a spectacular playground for adventurers. The six-hour tour traverses privately owned Kipu Ranch, a 4,000-acre working cattle ranch that’s been the backdrop for Hollywood blockbusters such as "Jurassic Park," "The Descendants," "Raiders of the Lost Ark" and "Pirates of the Caribbean."

Cesare Lucente, Outfitters Kauai’s general manager, and Rick Haviland, the company’s co-owner, designed and helped build the course, which wows even guests who’ve spent a lot of time outdoors.

"When Rick and I were planning the zip lines, we had to consider the topography because we needed adequate clearances and elevation changes from the launch to the catch sides," Lucente said. "But we also looked for locations with fantastic views. As we were pounding nails into the platforms, we imagined guests standing there, looking around with their eyes wide open, saying, ‘I’ve never seen anything as beautiful as this!’ And that’s exactly what happened!"

Opened with six lines in 2009, the tour was originally called the Zipline Trek Nui Loa and lasted four hours. In early 2012, work began to reconfigure three of the lines and to add three 1,000-foot tandem lines to up the thrill factor. The tour was reintroduced in December as the Zipline Trek Nui Nui Loa.

"Nui means ‘big’ and loa means ‘long,’" Lucente said. "We added another ‘Nui’ to the name to emphasize that the tour has faster, longer and higher lines, making it even more fun, scenic and exciting than before."

The Zipline Trek Nui Nui Loa features three experiences that aren’t available anywhere else in Hawaii, including "zippelling," a combination of zipping and rapelling. Participants move backward on a 100-foot cable, passing a 20-foot waterfall to get to the next launch site on the deck of a treehouse nestled in the branches of a giant banyan.

"When our guests start to zippel, they’re so close to the waterfall, they can feel the spray," Lucente said. "Most of them have never rappelled before, so this gives them an introduction to it in a safe, controlled environment. They determine the speed of their descent by adjusting the rappel rope."

Instead of going from platform to platform in the usual setup, riders on the tandem "center dismount" lines glide toward the end of the cables until gravity brings them to a halt. They then slide back down, coming to a stop at the cables’ center or lowest point, where a guide helps them step onto a platform using a double-sided ladder.

"This system allows them to reach faster speeds, hang upside down and zip backward because there’s no danger of hitting a platform at the end," Lucente said. "The Nui Nui Loa tour’s longest line is an 1,800-foot center dismount line, which most people cross in 90 seconds."

According to him, participants love the tour’s splashy conclusion, called the WaterZip. Holding a T-bar, they cruise 30 feet across the line before plunging into a waterfall-fed pool bordered by bamboo and white ginger.

"Imagine you’re Tarzan or James Bond," Lucente said. "The drop from the cable isn’t high — maybe about six feet — and the water is always cool and refreshing."

Participants don’t have to be athletic to zip. Aside from age and weight requirements, it’s an activity just about everyone can enjoy.

The Zipline Trek Nui Nui Loa was designed to be a progressive adventure that keeps guests guessing about what they’re going to do next. It starts with a series of low, short lines beneath the canopy, then moves upland to longer, higher lines over valleys, rivers and treetops.

"We’re constantly thinking about ways to make the rides more fun, different and challenging," Lucente said. "Our lines aren’t repeats in similar locations. The environment and methods of taking off, zipping and landing vary. We want our guests to leave with a sense of accomplishment. We want them to step out of their comfort zone and have a great time doing something they’ve never done before."

Shortly after Outfitters Kauai began offering the Zipline Trek Nui Nui Loa, Lucente recalled watching a woman pacing the launch platform of the first line above the canopy. Tears welled up in her eyes as she tried to subdue her fear of heights.

With encouragement from the guides and other participants, she finally summoned enough nerve, stepped off the platform and soared to the other side. Lucente chatted with her at the next line, where, buoyed by an adrenaline rush and newfound confidence, she was eagerly awaiting her turn to zip again.

"It’s so rewarding to see how exhilarated people are after they’ve zipped a line," Lucente said. "Countless times, I’ve heard them say, ‘I can’t believe I did that!’ or ‘I can’t believe my — fill in the blank with boyfriend, girlfriend, wife, husband, mom, dad, grandma, grandpa or kids — did that!’ After you’ve done the Zipline Trek Nui Nui Loa, everything else seems a little less exciting."

Cheryl Chee Tsutsumi is a Honolulu-based freelance writer whose travel features for the Star-Advertiser have won several Society of American Travel Writers awards.