Like many geographers, I am an outdoor enthusiast. From my childhood days at Hardin Ridge Recreation Area walking along well-planned and marked trails, I advanced to vast wilderness areas for both work and play. Usually with me were maps and navigation tools like a compass and GPS. This was before I was a professional geographer, so it never occurred to me how these maps and tools worked—they just did. In this article, we’ll explore how these maps are made and deployed, both on paper and digitally.
There are countless maps of trails and outdoor areas across the U.S. Some, like the National Park Service brochure maps, are for general planning and reference, and, like many of the ones I have made, state clearly: DO NOT USE FOR NAVIGATION. Others, like the ubiquitous USGS 7.5-minute topographic maps, Avenza Maps and the National Geographic Trails Illustrated maps, are excellent navigational tools, as long as the traveler knows how to use them properly.
Reliance on maps and GPS technology has many benefits and many pitfalls. On a personal level, my only bad experience was minor. Using a USGS topo map, my party and I navigated to Toad Lake only to find a wet meadow. We checked the metadata on the map and discovered it was published 13 years before! There were lots of toads there, but no lake.
“Death by GPS” has become a phrase to describe naive reliance on technology for navigation, and even seasoned professionals sometimes fall prey to it.
On a wildland fire incident, a crew needed a pick-up after dark. They radioed in their GPS coordinates and we plotted them on a map. It didn’t look right; they were three miles away from the pick-up point! Parsing the coordinates, it occurred to me—they were calling in degrees-minutes-seconds, when their GPS was set to degrees-decimal minutes. I replotted the coordinates and we asked them to describe their location. They were right where they should have been. It was a happy ending that could have gone very badly.
Maps at all scales
Managed by the State of New York, the six-million-acre Adirondack Park is the largest in the lower 48. Unlike many other parks, it has private inholdings and commercial services in over 100 settlements. In 1980, it was the site of the winter Olympics in Lake Placid, and the facility is still in use as a training venue. It is a beautiful landscape, and with its proximity to America’s largest urban area, it is heavily visited, so stewardship and management are critical to maintaining its wildness while accommodating millions of visitors every year, in all seasons.
The Adirondack Park Agency’s GIS program has developed a robust site with links to interactive maps, printable PDFs, downloadable GIS data and statistical reports. Some products, like the Park Visitor Interpretive Center Map, are meant for the public, while others, including Military Training Routes and Land Cover, are targeted toward professionals for both visualization and analysis.
At the federal level, all of the major land management agencies produce many types of maps for recreation. They range from the national level, like the one on my office wall (Do not use for navigation!) to maps of a single wilderness area, or a campground, or an individual trail. Most began in the pre-digital age, and have been updated to incorporate GIS data from various sources.
My colleague at the Bureau of Land Management is a full-time cartographer who only dabbles in GIS; most of the data he uses for maps are well vetted by the GIS staff, so he gets to spend his time making awesome maps for both public and staff use. Most of the public-facing maps for the National Park Service are made centrally at Harpers Ferry, but many parks make their own for local use.
Drilling down to the local level, our students at the college have made maps of running and hiking trails on campus and in the city, and one of them did a cost-path analysis of proximity to parks in the city, showing which neighborhoods were more than a ten-minute walk from a park.
The best cure for despair is action!
For years, my wife Wendy hiked the high peaks of the Adirondacks, and the wilderness in Oregon and South America. Wendy’s wilderness adventures came to an abrupt end in 2001, when an injury left her barely able to walk. We couldn’t hike or kayak together anymore—or could we?
Once back to work at the NPS, Wendy immersed herself in learning about the Americans with Disabilities Act and the Outdoor Developed Areas guidelines. That was good timing, since the park was putting in a new trail that had to be, by law, accessible to people with disabilities. It was a rewarding effort in teamwork. Wendy and the trails supervisor were the brains behind the design, and the hard-working trails crew did all of the heavy lifting. My duty was to map the trail path, taking sub-meter GPS points of the various benches and of surface compactness sample points along the way. From these efforts we created a map of other accessible trails in the park, which were distributed at the entrance stations and visitor centers.
Stop stepping on the plants!
Not all trails are defined or planned. Also called “user-defined trails,” social trails are ones that people make themselves, and are unfortunately prevalent in national parks. With a GPS, I mapped the social trails around the rim of Crater Lake, and then ran a coarse spatial analysis. Two patterns emerged, neither surprising. Social trails were more prevalent in turn-offs with a view of the lake, and the larger the size of the parking area, the greater the area of user-defined trails. In some places with large parking areas, they weren’t even trails at all, just large areas denuded of ground vegetation.
The U.S. Forest Service manages millions of acres of wilderness, in which there are thousands of miles of trails, and they are mostly without protection staff. However, they have developed a GST-based “Minimum Protocol for Social Trail Monitoring in Wilderness” in order to “inventory and assess the majority of social trails within a wilderness.”
Point, line or polygon?
One of my most enjoyable, and challenging, missions when building a ground-up GIS database was mapping county and city parks. Aside from a trusty Trimble and a paper basemap of park locations in the county, we were on our own. There was no database structure in 1997. We knew the fee station was a point, but was the boat ramp (on a river with fluctuating water levels) a point or line? Was the playground a point or a polygon?
Those questions brought my intern and me back to the essentials of cartography. For whom were we making this map? These data weren’t going to be used for spatial analysis; they were going to be used to make maps for the public and at stakeholder meetings.
Years later when I came to the National Park Service, it was more structured, but there were many aspects subject to interpretation. My colleagues and I spent many hours discussing how one database standard could be used for all of the 400+ units in the NPS. The National Mall is in a metropolis, while Glacier Bay spans thousands of acres of wilderness.
Could one data standard or data model be inclusive of all of these different places? How could we account for trails that were only open seasonally, due to snow or inundation or wildlife protection? I left the NPS before the full development, but the approach was to keep the actual feature class attributes minimal, then use linked tables for the many other attributes. The granularity was determined at the park level; some used existing base maps, some used GPS at various levels of accuracy, others used lidar.
Don’t just sit there!
Before closing, I’ll offer just a few of the resources available for planning and mapping trails. American Trails offers live and recorded webinars, with topics such as UAS and lidar. The Eppley Institute at Indiana University uses GST for park planning at all scales as well as statistical analysis.
In some places, like southern Indiana, it is already spring; in other places like Crater Lake, it is still winter. Wherever you are, there is never a bad time to get outside and explore. Whether you are in a city or out in the wild country, there is going to be a map to guide you. It doesn’t matter if you are wearing boots or sandals, riding a bike or using a mobility device. There is always some place to explore, so grab a map and go!