Settlers heading west in the mid-1800s gravitated to the large expanse of gently sloping terrain in what is now west-central Wyoming. For those traveling by oxen and covered wagon, this South Pass route was the easiest way through the formidable Rocky Mountains.

Today, peace, quiet, and miles upon miles of uninterrupted views draw visitors to the area. And the Bureau of Land Management’s Lander Field Office in Lander, Wyoming, is making sure it stays that way.

To maintain this pristine setting, the Lander Field Office released an updated resource management plan last June, which established a unique National Trails Management Corridor—the first plan in the country to protect not just the physical remains of the trails, but the entire viewshed.

It’s a monumental undertaking, but an important one. Four historic trails—the Oregon, California, Mormon Pioneer, and Pony Express—converge in the Lander region. The Seminoe Cutoff connects them to the Continental Divide National Scenic Trail. Together, these passages help tell the story of Western expansion.

“It’s quiet,” says Kristin Yannone, a planner with the Lander Field Office. “You can go out there and be still and only hear the critters. And as far as the eye can see, there’s nothing. It’s a powerful experience.”

Using a computer-generated simulation, the office assessed what could be seen from the trails, limiting surface occupancy and rights of way. No surface oil and gas development is permitted, and roads or power lines that are visible from the trails are banned.

Typically, trails in other parts of the country are protected by a buffer ranging from a quarter of a mile to a mile of land on either side. But, Yannone says, that’s a narrow focus. “What the settlers saw is what we’re trying to protect,” she says. “Segments of trails are lost all over, through mining, highways, pipelines, wind energy development. What this plan does is pretty extraordinary.”

The new plan protects more than 480,000 acres of land, used each year by upwards of 70,000 hikers, history buffs, and re-enactors, such as the young members of The Church of Jesus Christ of Latter-day Saints who retrace the steps of early Mormon pioneers.

This summer, the Lander field office hopes to introduce a new GPS-enabled smartphone tour of the trails. Visitors will be able to download the tour to their phones, which will alert them to nearby historic or geologic attractions and provide photographs, maps, narrations, and excerpts from pioneers’ diaries.

“This is a different kind of historic experience,” Yannone says. “We often use buildings to imagine early experiences. But these trails? This is where [the pioneers] walked. This is what they saw.”