I’ve always loved the visitor maps you get when you visit a national park. I’ve got little stashes of them tucked into the seat back pockets of my car and hidden away in closets. I can never bring myself to toss the maps when I get home from a trip. With their combination of photos, maps and text they bring back memories of where I’ve been and inspire me to think of adventures still waiting to be had.

Tom Patterson is one of the people who makes those maps. He’s visited more than 100 national parks, including some of the most far-flung and least visited. As a senior cartographer for the National Park Service, it’s Patterson’s job to make sure the maps visitors see at U.S. national parks, monuments, battlefields, and other sites are up to date and easy to use, even for people who aren’t cartographically inclined.

View Images The judicious use of shadow makes the Washington Monument stand out on this map of the National Mall. National Park Service

“We design our maps for a broad cross section of humanity,” Patterson says. “We believe very strongly that to get park visitors to look at a map, the first thing it has to be is pretty.” He and his colleagues try to design maps that draw people in with their good looks and keep them looking long enough to absorb some of the information they need to need to make the most of their visit—the location of trails, viewpoints, lodging, and so on.

National Park visitor maps have a certain look that makes them easy to recognize. That’s very much by design (and we’ll get to how it’s done), but it wasn’t always so.

Before World War II, most visitors arrived by train, Patterson says. Most of the maps in those days were made not by the park service but by railroad companies hoping to inspire people to take the trip. The latter half of the 20th century saw the rise of the automobile, and road maps became increasingly common. But it wasn’t until the 1970s that the Park Service began to standardize park visitor maps and give them a more uniform appearance. “Up to that point, there was a whole hodgepodge of different styles,” Patterson says.

View Images Natural colors on this map of Kenai Fjords National Park in Alaska help orient visitors to what they see around them. National Park Service

You can see a pictorial history of National Park visitor maps in the gallery at the bottom of this post—it’s a compilation of vintage park maps photographed by Nancy Haack, a (now retired) Park Service cartographer.

In 1977, the park service hired Massimo Vignelli, the graphic designer who created the iconic map and signage for the New York City subway system, and charged him with creating a more consistent style for the park system’s maps and other publications.

One design element Vignelli introduced is the bold black title band you can see on nearly all park service publications. “It’s become more or less part of the identity of the entire National Park Service,” Patterson says.

View Images The usually unseen unigrid (blue lines) organizes the layout of all National Park maps. National Park Service

The band is part of the “unigrid,” another of Vignelli’s innovations, still in use today. This grid guides the layout of every map, but it’s invisible in the final product (you can see it overlaid on the map of Theodore Roosevelt National Park above). “The maps look very organic but there is this hidden grid dictating the placement of photographs, text and maps,” Patterson says.

Another feature that distinguishes park service maps is their use of shaded relief to give the maps a 3-dimensional look. This method—using shading to simulate the shadows cast by hills and other features of the terrain—is Patterson’s specialty. He’s invented several techniques for doing shaded relief and even writes a blog about it.

The Park Service prefers shaded relief to contour lines, another way to portray 3D features of the terrain on a flat map. Each line follows a certain elevation—200 feet above sea level, for example. But the lines add “graphical noise” to a map, Patterson says, and many people don’t know how to use them. “Frankly, they look technical and not inviting.” (That said, if you’re hiking off into the backcountry, you will definitely want a topographic map—the visitor maps are just for basic planning).

View Images Shaded relief makes this map of Canyonlands National Park look surprisingly three-dimensional. National Park Service

Many other features of the visitor maps have been standardized as well, from the text (the house font of the National Park Service, and the only one to appear on its maps, is the clean-looking and highly legible Frutiger), to the symbols. There are currently 229 symbols used on Park Service maps to indicate everything from parking lots and campgrounds to various hazards that visitors might encounter.

View Images Easily recognizable symbols help park visitors find their way around. National Park Service

Most of the symbols are easily recognizable, even if some are a bit anachronistic. Like the boombox. And the tent. “I haven’t seen a tent that looks like that in quite some time,” Patterson says. “It looks like something from World War I.”

Sometimes a park will request a new symbol that tests the cartographers’ creativity, such as a symbol to indicate a zebra mussel decontamination station. Parks have these checkpoints to stop the spread of this invasive species. But Patterson says he couldn’t think of a good symbol for it, especially given the 3.5-millimeter size at which it would appear on a brochure. “Finally I just gave up and put a big Z in there,” he says.

Patterson is always experimenting with ways to make the maps more usable for people who aren’t very experienced at using maps. For some parks, he’s used natural colors from satellite photos so that the colors people see on the map match up with the terrain they see in front of them.

He and colleagues also use aerial photos to make detailed maps of historical sites. For the map of Fort Stanwix National Monument in upstate New York (see below) they hired a helicopter to photograph the site. It cost about $1,200 to hire the helicopter, Patterson says, but it probably saved $20,000 to $30,000 compared to the cost of drawing everything from scratch.

View Images Photographs shot from a helicopter became the basis for this visitor map of Fort Stanwix National Monument. National Park Service

More detail isn’t always better, though. Certain things don’t appear on parks’ visitor maps, including employee housing and parking areas, sensitive habitats, and some archaeological sites. The act of Congress that created the National Park Service 100 years ago specified that the service conserve the natural and historical resources of the parks as well as provide for the enjoyment of them.

Making maps that help fulfill that mission is a never-ending process, especially given the diversity of the parks’ visitors—more than 300 million of them each year—and the diversity of the parks themselves. The Park Service administers 411 units from Gates of the Arctic National Park and Preserve in Alaska to the National Park of American Samoa, south of the equator. Every map is custom made, Patterson says. “One-size-fits-all design doesn’t apply.”

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