Cell Phone Coverage Maps

Please note that these coverage maps are very coarse. The best way to get authoritative information on their coverage is to call your carrier about your specific plans. Most coverage maps are based on zip code. However, it's often difficult to find the zip code of some rural, backcountry location.

The Nextel site has this disclaimer, which resembles those of all other carriers: Coverage shown on the coverage maps is a general prediction of outdoor coverage, and does not guarantee that coverage will be available at all covered geographic areas at all times. Wireless coverage is impacted by, among other things, terrain, weather, antenna location, system modification, foliage and man-made structures (such as buildings), and therefore cannot be predicted precisely at all times.

• Cingular
  If you enter your zip code into this page, you can also see a more detailed regional map.
• Nextel
  If you enter your zip code into this page, you can see their rates. Along the top of that page is a link to a local coverage map for the zip code area you entered.
• Sprint
  If you enter the zip code into this page, you can see a more detailed map of that area.
• T-Mobile
  This page has a nifty coverage map that allows you to zoom and scroll. It's actually the most detailed and informative coverage map for any of the carriers I've seen.
• Verizon
  They also have an interactive coverage map, but you have to start by entering a zip code or a city name on this page.

Satellite Phones

There are two large networks which cover the U.S. Though they'll work where cell phones won't, you need a clear view of a large percentage of the sky to get a reliable connection.

• Globalstar
  They show coverage on almost all land areas of the northern hemisphere. Their smallest and lightest phone also weighs about a pound. Their airtime rates a low-volume plan are around $1.00/Min.
• Iridium
  They boast total coverage of the earth. The smallest and lightest phone weighs about 14 ounces. Their airtime rates for a low volume plan are around $1.75/Min.
• Satellite Phone Rental [Google Search]
  Many companies rent satellite phones on a weekly or monthly basis for around $50/week.

Amateur Radio

Ham radios have the potential to work from very remote locations. But they're a very do-it-yourself proposition that requires a government license to be legal, and then training and informed gear selection to be useful.

• Amateur Radio relay League (ARRL)
  This is the national advocacy organization for amateur radio. They sell training materials for getting an FCC license. They also provide a directory of courses and licensing examination locations.
• W5YI
  Another organization that offers training and conducts FCC approved licensing examinations all over the country.
• The Adventure Radio Society
  "ARS promotes a sense of adventure by supporting radio operation from beautiful and remarkable places. We sponsor events that encourage the use of human-powered travel, in its myriad forms, to reach outdoor operating sites."
• Federal Communications Commission (FCC)
  This is the FCC page about amateur radio. It's pretty dry reading, but it is the official source.
• Ham Radio FAQ for Thru-Hikers
  This is a page on Bill Jeffrey's Pacific Crest Trail Repeater Guide site. It talks about the pros and cons of amateur radio and other forms of communication for backcountry travelers.