I know that topographic maps and non-digital navigation can be intimidating, especially for those who never used them. In this guide, I'm going to focus on the basics of the topographic map so that you can look at one and make sense of it if your electronic fails.
In this Guide:
Topo Map General Concepts
Identifying Specific Landforms
Picking the Right Map For Your Hike
Topographic maps are also known as "topo maps" or "contour maps."
What Are Topographic Maps?
Topographic maps translate three-dimensional land features into a two-dimensional (flat) map. You can look at a topographic map and quickly see where the hills, rivers, peaks, and valleys are. When you are navigating, a topographic map can show you where you are, what route to take, and which ways are dead ends.
People generally pronounce topographic as TA-PAH-graphic and topo as TOE-PO.
The first country to be mapped entirely with topographic maps was France in 1789, while in the USA, the U.S. Geological Survey (USGS) just started the process in 1879. The first maps were based on sketches that surveyors made using analog tools to measure distance, angles, and elevations.
Look for these survey markers on your hike, especially on summits (there's a database of all of them in the USA here). They were put there by a human that was surveying to mark an important point for reference. From these markers, surveyors can then calculate other points in the surrounding area.
It wasn't until the 1930s that aerial photography was incorporated to make the maps more accurate. Today, the USGS doesn't do human surveys anymore but instead uses satellites and drones to update the topographic maps every three years. And as you probably guessed, today's maps are all digital but can still be printed out.
You can view the latest and greatest USGS topo maps on TopoViewer website. You can see all the map versions of the visible area on the right sidebar. Here you can see the oldest map of Mt Whitney that you can view online dates back to 1907 .Topographic maps are not just produced by governments, but also by commercial entities. Google Maps is one that you may have heard of. Their maps usually use elevations from multiple sources, including the USGS and commercial satellite data. While not openly publicized, inside sources hint that Google Maps elevations are heavily dependent LiDAR readings, measured from space with a pulsed laser that can penetrate tree cover.
Are We Talking About Printed or Digital Maps?
Although topographic maps were originally only printed, today they are available as digital maps or printed. When most people say "bring a topo map with you" they are referring to a paper map. But whether the map is digital or printed, the concepts and how to read the map are the same. I'll talk more about the actual maps that you should use later.
How To Read a Topographic Map
There are a few key concepts you need to know to understand a topographic map. It's easier than you think.
CalTopo now charges to download KMZ overlays, but you can get them for free from USGS. There's a how-to at the end of this article. I also have a sample you can download here.
What Are Contour Lines?
Contour lines are the key to topographic maps, and are lines that mark a specific elevation (like hillsides and mountains). Everything along a contour line is the same elevation, at least on the map. Theoretically, if you hiked along a contour line, you would never go up or down.Here's a great example of contour lines. The darker lines, marked with elevations, are called index lines. The number on an index line is the elevation of that line. The elevation is the same along the entire length of the line.The fainter intermediate contour lines between index lines are not labeled, but instead follow the contour interval. Printed maps will tell you the interval on the map key. In this case, it's 80 feet, so every fainter line is 80 feet higher or lower than the one next to it. Most topographic maps have an index line for every 5th line.If you have a printed map, look for the contour interval listed on the bottom. If you are looking at a digital map, you can usually click (or right-click) on a point to get the elevation based on the contour lines.Here's a flat topographic map laid over a Google Map 3D model. You can see that the lines match the slope of the mountains and canyons.
Want to overlay topographic maps onto a 3D Google Earth model so you can explore yourself? And even put your hike route on there? I'll show you how at the end of this article.
The closer the contour lines are together, the steeper the slope. The wider they are apart, the more gradual the slope.
While contour lines may "stack up" on a steep cliff, they otherwise never cross on another.
And remember that contour lines are models of the earth. If a slope has a 60 foot cliff like this, it won't show up on a map with 80-foot contours. Photo WikimediaHere's a topo map laid on top of a 3D surface in Google Earth. You can see that the trail which crosses no contour lines is flat, while the trail that runs across the contour lines is steep.Here's a regular, top-down view of the same area from the last image, as you would see it on a topographic map in 2d.
Reading Land Forms From Contour Lines
Let's start with the basics, a flat area, a steep slope, and a cliff.
In the middle, the contour lines are non-existent, meaning the area is flat. On the right, the contour lines are close to each other, meaning a steep climb. And on the left, the contour lines are stacked on top of each other, meaning a vertical cliff. Note the trail to the left Mile 145, which zig-zags up the slope. A zig-zagging trail is usually switchbacks, and is a clue that the climb is steep.Here's another view of the last image, this time overlaid onto a 3D surface area.And because most people wonder about it, here's the classic example, the Grand Canyon. Notice how there are many levels of steeply stacked contour lines between the top and the Colorado River below.Here's what the contour lines look like mapped into Google Earth, looking up from the river to the top. Lots of close contour lines mapping onto cliff walls and steep slopes.
Mountain Peak
Here's the mountain peak of Mt Harwood. Notice how the contour lines get smaller and more circular as they reach the peak. In this case, the peak has also been surveyed and has an elevation, 9552 feet.Here's Mt Harwood in a 3D view. Also, note that the wider top circle depicts a wider, flatter summit.
Double Summit
Gully / Ravine / Canyon
Look for V or U-shaped contour lines to spot a canyon or gully. The more like a V that the contour lines are, the steeper the walls, while a U-shaped formation has less steep sides. These formations usually have a creek or water sources flowing down them as well. The U or V will always point uphill.
Ridge Trail
At first glance, it looks like any trail in this area will involve climbing. But if you look carefully at the Pacific Crest Trail, you'll see that it almost follows the contour lines exactly, meaning that it's (theoretically) pretty flat.
Saddle / Gap / Notch / Pass
To spot a saddle or pass, look for an hourglass shape on the contour lines.
Cirque / Bowl
The natural amphitheater look of a bowl or cirque can be spotted by looking for steep and circular contour lines.
Features on Topographic Maps
Luckily most features on a topographic map are easy to interpret. Here you can see roads, trails, streams, and buildings.
I'm not going to give you an exhaustive list of every feature on a topographic map in this guide, but I will point out some of the more useful features to be aware of on your map. If you want to deep dive into all the features, the USGS has a comprehensive map key here.
A topographic map will not show all the terrain features. Landscapes change and what a mapmaker can fit on a map is limited.
Solid green means that the area is mostly covered by TALL vegetation such as a forest. White at the top of contour lines means an alpine zone where the trees have stopped. White in a flat area means a lack of tall vegetation, which could be grass, dirt, desert, etc. Looking at the elevations on a topo map will give the green areas some context.
A white area also doesn't mean a complete lack of vegetation. There could be grass, meadows, or even overgrown vegetation in a gully.
Blue features are usually water, as you can see by the lakes and streams here. When you see blue contour lines, it indicates a glacier. Standard contour lines are brown.Short black dashed lines are trails. Short black double lines are dirt roads. Do not make the mistake of thinking that the other dashed lines, which are boundaries, are trails.Who named all this stuff? The U.S. Board on Geographic Names was set up after the Civil War to standardize names on maps. Anyone can petition them to have a landform named, including the public. You just need some provenance to back up your claim.
Distance on Topographic Maps
I'll talk about scale shortly, but for most beginners, a key aspect in reading a topographic map is understanding how far apart things are.
At the bottom of almost every map is the scale measurement. Even digital maps will have a scale (that changes as you zoom) on the bottom.Once you know what the scale is, you're going to want to measure the trail. The only problem is that trails generally twist and turn, while the scale is straight. A neat trick is to lay a lanyard or shoelace along your route. Then you can straighten it out and lay it against the scale key to find the distance.Some maps, like these from National Geographic, include the trail distances on each segment, which is very handy.
A mile, or 5280 feet, is derived from the distance that Roman soldiers would walk in 1000 (double) steps. The Latin word for thousand is mille, which the word mile is derived from.
Using Printed Topographic Maps
As I mentioned earlier, there's a solid amount of hikers who just use a GPS, whether on their phone or on a dedicated GPS unit. If you fall into that category of hiker, I strongly recommend bringing a printed topographic map with you in case your device fails in the backcountry. Even if you don't know the more advanced skills like orienteering, navigating, or route finding, the paper map is still helpful.
You'll likely know where you want to hike. And now you know how to read a topographic map. From there you can look at the map, your surroundings, and your expected position, and figure out a course of action if your GPS dies. For the cost of a $12 map, you have an invaluable resource if the electronics fail.
Here's what I recommend for those who are GPS-dependent or are beginners.
Buy a printed map for the area that you are hiking.
Look over the route on the printed map before you go.
Fold the printed map to show your route and carry it in your pocket as you hike. Periodically take the map out and see if you can orient yourself. Trail junctions and physical landmarks are a good place to do this.
To make things simple, think of map scale as how much detail is covered on a map.
On a "small scale" map like this NPS visitor map, which covers the width of Grand Canyon National Park, at about 300 miles, the level of detail is minimal. In other words, small scale is small (or less) detail.On a "large scale" map like this topo map, more detail is shown. On a map like this, each inch is about ⅓ mile. "Large scale" equates to a large amount of detail.
The common sizes for printed hiking topo maps are:
1:24,000 - The USGS has mapped most of the USA at this scale, and they're often referred to as "7.5-minute quadrangle" or "quad" maps. They cover an area of about 6 by 9 miles, and every inch is about a third of a mile. If you get them printed out (you can buy them online), they come on big 22 x 27 inch paper that you need to fold up. And for longer hikes, you will likely need multiples.
1:50,000 to 1:100,000 range - For most hikers, this is the sweet spot for a topo map, and the scale that most commercial maps (like Tom Harrison or National Geographic) come in. At 1:63,360 scale, 1 inch equals 1 mile. Generally these maps come folded for easy use.
Decoding scale is easy. The first number is an inch on a printed map, the second number is the number of inches it represents in real life. So a 1:24,000 map would show 24,000 inches (0.38 miles) for every inch of paper.
Map Recommendations
While you can custom order maps from the USGS, it's usually easier to buy a third-party map that's designed to cover a specific area like a park or mountain range, and which are often water-resistant.
Here's what I would recommend if you're just getting into carrying a paper map.
Buy a foldable map with hiking trails that has a scale in the 1:50,000 to 1:100,000 range. There are regional map brands like AMC, Tom Harrison, and Green Trails. And then there are maps with national coverage such as National Geographic.
You can also order USGS quads directly for a reasonable price. Remember that you may need to buy multiples to cover your hike. And not all trails are these maps. They are, however, probably as detailed as you can get when it comes to topography. I'll use USGS quads when I'm going overland, but otherwise I'll use a third-party map for a region.
You can use a website like CalTopo to create a custom area and print out scanned topo maps.
Digital Maps
I mentioned earlier that topographic maps were available digitally as well. Digital maps throw a little wrench into the idea of scale. If 1 inch equals 1 mile on a 1:63,360 map, what is 1 inch on a screen? What I can see on 1 inch of a screen on a phone from 2010 is much different then on a high-resolution screen from today. And you can zoom in and out on digital maps too. So how does that all work?
It's basically a matter of detail that's included. For example, Garmin sells 24k (roughly equivalent to a quad topographic map) and the 100k TopoActive maps. The 24k maps include more detail than the 100k maps. But for most free digital maps, the level of detail is as detailed as it can be. And most modern map browsers let you tweak the level of detail on a map or do it automatically for you.
In the Garmin Basecamp program you can use the slider at the bottom to control the level of detail that you view on a map.
Digital Map Options
You aren't limited to the maps that that USGS produces when it comes to digital topographic maps (which you can print). Tools like Gaia GPS (discount code here) and CalTopo allow you to view alternate topo maps and print them. You can even customize the maps to include other layers such as snow cover, weather, etc. It's very powerful. Let's look at some of the better digital topographic map options, which you can print out or send to your device.
CalTopo - Mapbuilder Topo
The default map in Caltopo is the Mapbuilder Topo, which is based on several sources and updated 4 times a year. This is a solid map that also includes distances between trail segments.
CalTopo - Scanned Topos
Caltopo also has scanned USGS (in the USA) topographic maps. They may not be the latest, and they often don't reflect all the trails, but they are your best bet for landform names (like creeks, canyons, etc.).
CalTopo - Forest Service
In the old days US Forest Service maps had many more trails than the USGS maps, but today they are almost identical. Many people prefer the cartography choices on the Forest Service maps; it's less cluttered and busy than the USGS maps. The Forest Service maps don't have the UTM grid and do have all the Forest Service road numbers labeled, which is helpful.
CalTopo - TF Outdoors
The TF Outdoors map is a variation of the Open Street Map that's focused on the outdoors. These maps generally have lots of trails on them, but the quality of the trails can be variable. Sometimes the trails are small use trails, and other times they can be technical scrambles. For example, in this screenshot from Mt Whitney, the TF Outdoors map shows the Mountaineer's Route, which is not on the earlier maps and is not really a trail, at least in its tough ending. Some folks might think they can just take a nice hike up the line on the map, which is not the case without more context.
You'll also notice that this map has a combination of contour lines and shading, which is a computer generated way to illustrate slope, usually found on digital maps.
CalTopo - Global Imagery + Mapbuilder Topo
Another powerful map is combining the Global Imagery satellite map with the Mapbuilder Topo overlaid at 50% opacity. With this view you can see the natural features with the contours and trails on top.
Gaia GPS (Native Maps)
The (new) native maps in Gaia GPS are probably my favorites. They're based on multiple sources and the cartography has just the right level of detail and contrast for the outdoors.
National Geographic Digital (Gaia GPS)
This is the digital version of the paper maps. While not as detailed as the Gaia GPS native maps, they're still easy to read and great for navigating, especially over a larger area. These maps are available with a premium Gaia GPS membership.
AllTrails Native
AllTrails has proprietary topographic maps which are good. If you're using the AllTrails app already, generally your best bet is to use the default maps (pictured here).
Exploring Topographic Maps With Google Earth
The best way to really understand a topographic map is to take it with you on a hike, find your position. look at map, look at the features around you, and translate the map features to real-life in real-time. But if you want to practice at home (or when avoiding work), there's a cool trick that you can do with Google Earth that overlays topo maps onto the Earth's contours. It's a great way to prep for a hike and learn topo map features at the same time.
Step 1: Visit CalTopo and Get Your Topo Map
Note that CalTopo now requires a Pro account to download KMZ files. I think it's worth it, but if you're not intersted, you can also download them for free from USGS. I'll show that in the next step.
Go to the Caltopo website and find the area that you want to explore. Make sure you have "Scanned Topos" selected as your base layer.Click on Print and then Garmin Custom Map.Select the area to download with the red bounding box, then click download KMZ.
Step 1-Alt: Get Free KMZ Topo Maps from the USGS
If you want to download the topographic map files for free, just head over to the USGS Topoviewer site.
Select the area that you want and then choose a map version on the right. Once you choose your map, look for the KMZ link like I've got circled here, just under the map name.
The download from here may give you two files. Open them both in Google Earth to find which one is the topo map.
Start Google Earth and then load the KMZ file that you downloaded earlier.Zoom in with the controls on the right. Clicking on the small up arrow will move your perspective closer to the ground so that you're looking up.Go all the way down and look all the way up for an "on the ground" perspective." I've included the regular Google satellite photo on the left so you can see how the topo map adheres to the terrain.
You can load multiple KMZ files into Google Earth. Just download multiple areas in CalTopo and open them with Google Earth.
Step 3: Load Your Hike GPX File
If you are examining the area of a hike you're going to do, you can load your GPX file into Google Earth and it will be overlaid on your KMZ files.
When you open the GPX file with Google Earth, make sure that you have "Create KML Linestrings" checked.Find your track on the left side and double click on it. The view will adjust to encompass the track. I find it helpful to uncheck the "Points" to keep the view uncluttered.
Have a question about the guide or want to see what other people are saying/asking? View the Youtube comments for this video. Leave a comment and I will do my best to respond.
Hi, I'm Cris Hazzard, aka Hiking Guy, a professional outdoors guide, hiking expert, and author based in Southern California. I created this website to share all the great hikes I do with everyone else out there. This site is different because it gives detailed directions that even the beginning hiker can follow. I also share what hiking gear works and doesn't so you don't waste money. I don't do sponsored or promoted content; I share only the gear recommendations, hikes, and tips that I would with my family and friends. If you like the website and YouTube channel, please support these free guides (I couldn't do it without folks like you!).