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The coordinates of the put-in and take-out spots for each paddle, along with the coordinates for the nearest tide station (where applicable), are provided in latitude–longitude format. In this system, lines of latitude, or parallels, run horizontally across the globe, equally distant from each other. Each parallel, expressed in degrees, is roughly equal to 69 miles, although there is a slight variation because the earth is not a perfect circle but an oval. Nevertheless, the equator is considered 0°, while the North Pole is 90°N and the South Pole is 90°S.

Also expressed in degrees, lines of longitude, or meridians, run vertically on the globe, perpendicular to latitude lines. Instead of being equidistant, however, they converge at the poles. As a result, they are widest at the equator (about 69 miles apart) and become increasingly narrow as they move north or south. The Prime Meridian, in Greenwich, England, is designated as 0° longitude. From this point, the meridians continue east and west, until they meet 180° later at the International Date Line in the Pacific Ocean.

In this book, latitude–longitude coordinates are expressed in degrees and decimal minutes. For example, the put-in and take-out coordinates for Accabonac Harbor are as follows: N41° 01.115′ W72° 08.738′; N41° 01.115′ W72° 08.738′. These coordinates can also be expressed in degrees, minutes, and seconds. To convert from this format to degrees and decimal minutes, divide the seconds by 60. For more on GPS technology, visit usgs.gov.