Launched in 2009, the US Topo Quadrangles project provides free online quadrangle topographic maps for anyone living in the continental United States. Produced by the National Geospatial Program, these USGS topo maps are modeled after the standard 7.5 minute, 1:24,000 base maps that went into circulation shortly after World War II, allowing users to not only get directions but also be advised of whether they’re going uphill, downhill, or over flat land.
These maps are useful for hiking, camping, and rural road navigation. Each 7.5 minute quadrangle map covers an area of 49 to 70 square miles, which is a big area for a map that can fit on a small sheet of paper.
If you’re not familiar with topographic maps, you might get a little confused the first time you look at one. It’s filled with squiggly lines (called contour lines), but they can easily be deciphered once you know what you’re looking at. Watch the video below for a beginner course into topographic maps and contour lines.
A few of the things you learn from the video are:
- Contour lines, which always connect to form a circle, have the same elevation all through out. If you were to walk a contour line, your elevation would stay the same.
- Most contour lines will have the elevation number.
- One side of a contour line is uphill and the other is downhill.
- The area inside the contour line is almost always higher in elevation than the line itself.
- The smaller the circle the contour lines make, the higher the elevation. If a contour line creates a tiny circle with no more contour lines inside of it, it’s more than likely a peak of a mountain/ridge/hill/etc.
- Contour lines form a V pattern when they cross water such as a river or stream. The tip of the V points uphill while the other side points down.
- Contour lines on opposite sides of a valley or ridge always occur in pairs.
- Contour lines do not touch or cross each other.
Now that you’re a topo map expert, it’s time get to your hands on ’em!
Free Printable USGS Topo Maps From National Geographic
National Geographic has an easy-to-use interface that allows you to find a topographic map of your desired area in seconds with the help of an interactive map. From there you can download it and print and you’re ready to go. Head over to their website to check out the USGS topo maps.
1. Select topo map. Simply zoom in to your area and click on one of the red markers, which will bring up the topo map of the area.
2. Download map. The PDF will come with 5 pages: 1 with the entire area and 4 with the map cut into quarters. Below you can see a portion of the Taylor Canyon map from the Los Padres National Forest in California.
3. Print. Open the PDF and hit print. You’ll get 5 pages in total, as mentioned before. Keep them somewhere safe.
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from SurvivalLife https://survivallife.com/usgs-topo-maps/
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