Rail construction is designed wherever possible to avoid going uphill or downhill. When railroads build their lines, the surveyors identify the contour lines. When you follow a contour line, you are walking at a constant elevation.įlat trails are easy for hikers - and essential for railroads. You might get tired stepping over boulders and fallen trees, but you won't be walking uphill or downhill. If you chose to walk around the mountain on a path that followed the contour lines, you would follow the red arrow and be walking at the same elevation - neither uphill nor downhill. If you were walked up Big Cobbler Mountain and followed the black arrow, you would be walking uphill from 700 feet to 800 feet above sea level. Source: US Geological Survey (USGS), Orlean 7.5x7.5 topographic quadrangle (2013) (on this USGS map, contour lines are displayed for every 20 feet of elevation) There is a Big Cobbler Mountain, and a Little Cobbler Mountain, in Fauquier County.īig Cobbler Mountain is 1,562 feet above sea level There is a Cobbler Mountain in Bath County:Ĭobbler Mountain near Warm Springs in Bath County There is more than one mountain in Virginia named after cobblers, or people named Cobbler. There is more than one Blacksburg, and many "Little River" streams in Virginia. SECOND CAUTION: Virginians were not always creative when choosing place names they repeated themselves, and recycled names that had been used in other places. The contour lines are 40 meters apart on the maps in that atlas, compared to 20 feet apart on the 1:24,000 scale USGS topo maps. The scale of the DeLorme Atlas and Gazetteer maps is identified on the bottom of each page. One meter is roughly 3.3 feet, so 10 meters = about 33 feet, or roughly 10 yards. Source: US Geological Survey (USGS) Earth Observatory, Appalachian MountainsĬAUTION: maps are printed in different scales some maps measure elevation in meters rather than feet. Mountain topography - can you spot Massanutten Mountain, west of the Potomac River? Can you visualize topographic lines in your head, even when they are not displayed on a photo? Photos and radar images are not topographic maps, but they do allow us to "see" the mountains. If you use a radar sensor, you can see the mountains on an image without the clutter of all those contour lines drawn by a cartographer (or a computer.). Source: Architect of the Capitol, Boone at Cumberland Gap In 1775, the land speculators of the Transylvania Company paid Daniel Boone to blaze a path westward from Cumberland Gap into Kentucky's Bluegrass Region In the topographic map, did you notice the highway now goes underneath Cumberland Gap in a tunnel? Source: US Geological Survey (USGS), Middlesboro South, KY-TN-VA 7.5-minute topographic map The Native Americans in the area resisted, and Kentucky becane a "dark and bloody ground" as Cherokee chief Dragging Canoe had predicted. Daniel Boone and his axemen cut the Wilderness Road through the low spot in the mountain barrier in 1775, and settlers poured into Kentucky. That gap offered the easiest path through the Allegheny Front, in the 1700's. Source: US Geological Survey (USGS), Reference and Outline Maps of the United States - Rivers and LakesĬompare the topographic map and the aerial photo of Cumberland Gap, at the far southwest corner of Virginia. Major rivers and lakes in Virginia, with no contour lines or sharing to show elevation differences orchard - but get out your reading glasses, flip through a few maps, and get to know how to interpret the information. You need good eyes to distinguish the symbols on the maps for pipelines vs. The legend is the equivalent of a secret decoder ring for interpreting the lines and colors on the paper. The legend on the inside cover of the DeLorme Atlas and Gazetteer explains the colors and categories of information displayed on the map. Convert the metric units to traditional English units, and you'll discover that 40 meters is roughly 131 feet. Note that the contour intervals in the DeLorme Atlas and Gazetteer are in meters. Once you get the hang of it, you can see how the lines display the location of hills and valleys. Such maps show the elevation of mountains and valleys with contour lines, with the elevation differences represented by light brown lines illustrating the height of the land above sea level. The DeLorme Atlas and Gazetteer, like the 1:24,000 quadrangle (quad) maps of USGS, provides "topographic" (topo) maps. Source: US Geological Survey (USGS), Warm Springs, VA 7.5-minute topographical map (2016) Topographic map showing contour lines near Warm Springs in Bath County (contour interval: 20 feet) If your background is in another discipline, this might provide a useful refresher. NOTE: if you are a geography major, this material will be "old hat" to you. Get Familiar With the Brown Lines on the Topographic Maps Get Familiar With the Brown Lines on the Topographic Maps
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