How to Read a Map

Map & Compass

map reading. Photo by Georgette Weir.A good map in your pocket is a reliable tool and still highly recommended when venturing in the outdoors. It doesn't run out of power and you don't have to depend on satellite reception.  Basic compass skills also never go out of date. For an introduction to map and compass use, click here.

Compass caution in New York-New Jersey:  Be aware that the New York-New Jersey area is loaded with iron mines which locally make a compass almost useless. It is also worth noting that you will be off by about 90 feet per mile for each degree that you wrong. In other words ignoring the difference between magnetic north and true north is a serious error. The declination changes with time. Look at the date of the declination information on any USGS topo and be aware that it could be off by a few degrees if it is not a recent map.

 

 

UTM Grids: The New Way of Using Maps

Trail Conference Maps & UTM Grids All newer Trail Conference maps have a UTM grid. UTM is short for Universal Transverse Mercator, a common map projection. These are the fine lines with a square grid of 1 km (approximately 0.6 mile) on a side. These are useful for estimating distances at a glance. The map edge is marked vertically with the northing, e.g. 4588000N, and horizontally with the easting, e.g. 18T 585000E. The northing is the distance in meters north of the equator. The easting (minus 500000) is the distance in meters from from the center line of the zone. NY and NJ are in zone 18 (hence the 18T in the easting). The bold characters can be used to reference a paricular grid square, thus the trailhead of the Breakneck Ridge Trail in Hudson Highland State Park could be described as near 88x85. GPS users like UTM because if they know the UTM grid point of some location, they can enter into their GPS and navigate to that point (good for finding mines or airplance crashes).

 

If you get lost...