How to prepare offline maps for an emergency or trip

Download the area you will actually use

While you still have a reliable connection, download the region around your destination and any areas you may need to cross. Check that the download completes, that your phone has free storage, and that its battery or backup power is ready. A map of home may not include the next county, trailhead, or alternate destination.

Open the saved region before leaving and check what the app can still display without internet. If the device lets you select offline storage or update a map, review those controls in advance instead of during a disruption.

Check what navigation functions are available

A map image or downloaded place index does not necessarily include road-by-road routing. Some routing data may be a separate download or unavailable for a particular area. Check the app’s visible offline-availability notice and do not assume that a route can be calculated merely because the map appears.

Offline maps generally cannot show live traffic, newly closed roads, fast-changing hazards, or up-to-date evacuation orders. A saved route is a planning reference, not a live safety assessment.

Bring a paper backup and learn it before travel

The National Park Service recommends carrying a physical map as a backup and knowing how to use navigation tools before a trip. Conditions, your experience, and the route difficulty all matter.

• Carry an up-to-date paper map that covers the route and an alternate area.
• Mark the destination, key junctions, nearby town names, and a planned check-in point.
• Bring a compass if you know how to use one; practice reading the map before relying on it.
• Tell a trusted person the plan and when to raise concern if you do not check in.

Follow current alerts over an older saved route

Before you leave, check local weather, transportation, land-manager, and emergency-management information. During an incident, follow official road closures, evacuation orders, and safe shelter guidance—even if an offline route suggests a shorter road.

Do not drive or walk into floodwater, a closed area, or another hazard to test whether a map is correct. If an immediate emergency occurs, use the local emergency number or an official emergency service when possible.

Use offline maps as one layer of your plan

Pair a saved map with a communication plan, charged devices, emergency supplies, and a backup navigation method. Test your own offline setup in advance: downloaded map coverage, location access, storage, battery use, and whether the features you plan to use are actually present in that region.

Survive Link map downloads and offline routing depend on what data is available for the selected region. Missing routing data stays unavailable rather than being guessed. Check the in-app availability information before relying on a route.