Gear
Maps that say where you may legally drive, a way to find yourself on them without a signal, radios for the group, and a way to call for help when no phone will connect.
Getting lost is rarely the problem. The problems are driving a road that was never open to you, losing the group in the dust, and having no way to tell anyone that the truck is on its side forty miles from pavement.
This guide covers the maps that carry legal weight, phones and GPS units used offline, satellite SOS devices, the radio services and which of them need a license, and the plan you leave at home. No brands and no apps by name: judge tools by what they do.
This equipment does three jobs. It tells you where you are and where you are allowed to drive. It lets the vehicles in a group talk to each other. And it gets a message out when something has gone wrong and no phone will connect. No single device does all three, so think in layers, each one covering for the failure of the one before it.
Start by distrusting the coverage map. The FCC says mobile providers generate the coverage areas on its National Broadband Map with propagation modeling, and that what you get on the ground may differ with your device, the capacity of the cell site and the terrain. A carrier's own map may rest on other assumptions again, such as roaming. A shaded area is a model of open country, not a promise for the bottom of a canyon.
What matters when you choose: that it works with no signal, that you can power it for the whole trip, and that you have used it before you need it. Screen size and feature lists matter far less.
On a national forest, the map that matters most is free and plain. The Forest Service's Motor Vehicle Use Map (MVUM) shows the roads, trails and areas designated for motor vehicles, by class of vehicle and by season. The agency is blunt about it: a route that is not on the map is not open to motor vehicles even if it looks usable, routes are not always signed on the ground, and not following the map will likely result in a citation.
It is just as clear about the map's limits. The MVUM is black and white, shows no terrain, and is meant to be used beside a forest visitor map or another detailed map. It is updated as needed, so get the current one for each trip.
For planning at home, the public land map on this site (overlanding.life/explore/map/) puts land status, roads, trails and campgrounds in one view. Use it to see whose rules apply and where to look closer. It is a planning aid, not something to steer by.
The maps worth carrying
A phone is a good navigation tool on one condition: the maps must be on it before you leave coverage. The GPS receiver needs no cell signal. The map data does, unless you downloaded it. The BLM says as much about its own georeferenced maps: download them before you reach an area without data coverage, and a map app will show your position as a dot with no reception at all.
Judge any app by function. Can you download a whole region at useful detail? Does it load agency maps and show who manages the land? Can you record a track and follow it back out?
The BLM adds two practical points. A phone with no reception drains its battery quickly, and airplane mode stops that without interfering with GPS. And like all GPS, a phone loses accuracy close to tall cliff walls and in slot canyons.
A dedicated GPS unit earns its place where the phone is weak: heat on a dashboard, cold, dust, rain, a battery you also need for calls. A purpose-built unit is sealed, runs on replaceable cells or vehicle power, and keeps working when the phone is broken. It is a second system, which is the point.
There are two kinds of device. A personal locator beacon does one thing. NOAA, which runs the United States side of the international satellite rescue system, says a 406 MHz beacon has a single function, to alert search and rescue authorities directly that you need help, and that a personal beacon can only be set off by hand. It needs no subscription. NOAA stresses registering it, because registration tells rescuers who they are looking for and lets them rule out a false alarm with a phone call. Once activated, a beacon must transmit for at least 24 hours.
A satellite messenger runs on a commercial satellite network and needs a paid subscription to work at all. Its SOS goes to a monitoring center working for the service, which passes the call to the rescue agency responsible for where you are. What you gain is conversation. Two-way models let you say what is wrong, and let you send the message you will send most often: fine, but a day late.
Now the limits. SOS starts a rescue. It does not shorten one. Neither device moves a helicopter through a storm, and both need a clear view of the sky and a charged battery. NOAA also warns that setting off a beacon when you are not in distress pulls rescuers away from real emergencies. SOS is for a threat to life, not a flat tire.
Do not skipAn SOS device is the last layer, not the first. It does not replace water, shelter, a trip plan or the sense to stay with the vehicle.
Radios are for the group, not for rescue. They let a spotter talk a driver over a ledge and let a convoy spread out of its own dust without losing touch. All three services here are short range and work best with a clear line between antennas.
Use what the people you travel with already use, because a radio nobody else can hear is ballast. And stay legal: the FCC warns that operating a transmitter without the license it requires can bring fines and the loss of the equipment.
The three services
Amateur radio, or ham radio, is the most capable of the four and asks the most of you. The FCC requires every operator to hold a license, earned by passing an exam given by volunteer examiners, and says most newcomers start with the Technician class. Unlike GMRS, the license is personal. It does not cover a family.
In return you get more power, more bands, and repeaters run by local clubs that carry a handheld's signal well beyond line of sight. It does not help you talk to a group that is on GMRS, so settle the group's radio first and treat ham as an addition.
The cheapest communication device is a person at home who knows where you went. The National Park Service calls it a trip plan: a written plan given to a trusted contact who is not on the trip, with your route, what you are doing and when you expect to be back.
If you are overdue, the contact tries to reach you. If they cannot, they call the authorities and hand over the plan. The Park Service notes that a park will not hold the plan for you, that it is no substitute for a required permit, and that a search is badly slowed when the plan is wrong or the traveler has left the route written on it.
So write down the vehicle and its plates, who is aboard, the route with its bail-out options, and a firm time to raise the alarm. If the plan changes, tell your contact before you lose signal, not after.
Most failures are ordinary. Maps that were never downloaded. A subscription that lapsed over the winter. A beacon registered to an old phone number. A radio nobody programmed until the trailhead.
The larger mistake is treating any of it as a guarantee. The National Park Service tells visitors that search and rescue can take hours or days, depending on weather and resources. Plan to look after yourselves for that long.
Overland outfitters sell and install radios, antennas and mounts, and a careful installer fuses the power feed and routes coax away from pinch points. A navigation session in a training course is the fastest way to learn the gear you already own.
Before each trip
Yes. The FCC requires a license to operate a GMRS radio. There is no exam, the applicant must be 18 or older, the license runs for ten years and it covers your immediate family. The FCC's fee filing guide listed the application fee at $35 as of September 2026. FRS and CB need no license, and amateur radio needs a license earned by exam.
Yes, if the maps are already on the phone. The GPS receiver works without a cell signal, but the map has to be downloaded before you leave coverage. Put the phone in airplane mode to save the battery, which does not affect GPS, and carry a paper map in case the phone breaks or runs flat.
No. The Forest Service describes it as a black and white map of legal designations with no topographic detail, and tells you to use it alongside a forest visitor map or another detailed map. It answers one question, whether you may drive a route in your class of vehicle in this season, and a route that is not on it is not open.
On a personal locator beacon, a distress signal goes by satellite to government search and rescue authorities, and your registration tells them who you are. On a satellite messenger, it goes to a monitoring center that contacts the responsible rescue agency, and two-way models let you describe the emergency. Either way the National Park Service warns that a rescue can take hours or days, so stay put, stay visible and keep the device where it can see the sky.
They do different jobs. A beacon has no subscription and one function, a distress alert sent directly to search and rescue authorities. A messenger costs a subscription and adds two-way text, which lets you explain an emergency or simply report a delay. Choose by how you travel, register or activate it before you leave, and do not let either one stand in for a trip plan.
Yes. The FCC says all FRS channels are shared with GMRS, so a license-free FRS handheld and a licensed GMRS vehicle radio can talk on the shared channels. The GMRS radio must still be operated under a GMRS license.
Reviewed September 19, 2026. Conditions, closures and rules change; check with the managing agency before you travel.