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As a self-confessed lovers of land, the outdoors, and geography in general, we here at LJCK love maps. Paper maps, digital maps, reference maps, thematic maps - they represent the world we live on in a way nothing else can. As such, it is important that we dedicate a slice of this compendium to maps and all the good they stand for1).
Types of Maps
Two major types of maps exist, and though overlap between these types exists, it generally should be avoided.
Reference maps are what most people think of when they think of a map. A map of interstate highways you get from a rest stop is a reference map, or the classic National Geographic World Political Map. These maps demonstrate the connection between land and features on that land - roads, rivers, towns, political borders, etc. In short, a reference map is what you use to get from point A to point B or familiarize yourself with a region.
A thematic map is used to demonstrate one or more characteristics of a region. An example of a thematic map most people are likely familiar with is an election map; we've all seen them on news sites and TV: democratic states are blue, republican states are red, and so on. This map is not particularly useful in getting around within a geographic region, but it can convey information (in this example, electoral statistics) much faster than a table or chart might. These maps are incredibly dynamic and can convey many different types of information in many different ways. To put it simply: if it's a characteristic that can be attributed to a geographic region, it can be expressed on a thematic map!
Where to Get Maps
The type of map you are looking for depends a lot on where you can find it. The maps I use most when “in the field” so to speak (hiking, camping, geocaching, etc) are USGS 1:24k quadrangles. These are very large scale maps that show a tremendous amount of detail. The tradeoff is that they only show a relatively small area - 6 by 9 miles. That said, the vast majority of the contiguous United States is covered by these maps - and the USGS has them all available as GeoPDFs for free download! They can be found here, with the USGS MapLocator tool.