Reading Maps Without GPS

GPS is convenient, reliable, and fast — until it isn't. In a major emergency, phone batteries die, mobile networks overload, and satellite signals can be disrupted. The ability to read a paper map and use a compass is a fundamental survival skill that requires no battery, no signal, and no infrastructure.

This guide teaches practical map and compass skills from first principles, focused on the skills you will actually use in an emergency evacuation.

⚠️ Navigation errors in emergencies cost lives. Practice map and compass skills in non-emergency conditions before you need them. This guide provides the knowledge framework — physical practice is essential before you rely on these skills under stress.

---

Types of Maps

Not all maps serve the same purpose. Understanding what you have determines how you use it.

Map Type	Scale	Best Use	What It Shows
Street map (urban)	1:10,000 to 1:25,000	Urban navigation, evacuation routing	Roads, buildings, landmarks, transit
Topographic map	1:25,000 to 1:50,000	Rural and wilderness navigation	Terrain, elevation, water, roads, structures
Road atlas	1:100,000 to 1:250,000	Regional route planning	Major roads, towns, distances
Hiking/trail map	Varies	Wilderness routes	Trails, shelters, water sources
Flood/hazard map	Varies	Risk assessment	Flood zones, evacuation routes

For emergency preparedness, keep:

1. A current street map of your immediate area (urban/suburban detail)
2. A regional road atlas for your wider area (50–100km radius)
3. A topographic map if you live near or may evacuate through rural/wilderness terrain

Print emergency maps from government or national mapping websites and store them in your emergency kit in a waterproof sleeve.

---

Map Scale and Distance

The scale on a map tells you the relationship between map distance and ground distance.

Reading scale:

• 1:25,000 means 1cm on the map = 25,000cm on the ground = 250 metres
• 1:50,000 means 1cm on the map = 50,000cm = 500 metres
• 1:100,000 means 1cm on the map = 1,000 metres = 1 kilometre

Measuring distance on a map:

1. Use a ruler or the edge of your compass to measure the route distance in centimetres
2. Multiply by the scale denominator, then divide by 100,000 to get kilometres

Example: A route measures 6cm on a 1:50,000 map. 6 × 50,000 = 300,000cm ÷ 100,000 = 3 kilometres

Walking time estimation:

• Flat terrain: 1km per 12 minutes (5km/h)
• Mixed terrain with load: 1km per 20 minutes (3km/h)
• Add 10 minutes per 100m of ascent (Naismith's Rule)

---

Orienting a Map

A map is most useful when it is oriented to match the ground around you.

Method 1: Using the compass

1. Lay the map flat
2. Place the compass on the map with the direction-of-travel arrow pointing north on the map (toward the top of the map in most cases)
3. Rotate the map and compass together until the compass needle aligns with north (accounting for magnetic declination — see below)
4. The map is now oriented — features on the map should correspond to features in the landscape in front of you

Method 2: Using landscape features

1. Identify two or more features visible in the landscape (hill, road junction, building, river bend)
2. Find these features on the map
3. Rotate the map until the features on the map align with their positions in the real landscape
4. You are now holding an oriented map

Oriented map use: Once oriented, features to your left on the ground should be to the left on the map, features ahead should be ahead on the map. This makes route-following intuitive.

---

Compass Use

A baseplate compass (also called an orienteering compass) is the standard tool. It has a transparent rectangular baseplate, a rotating bezel with degree markings, and a needle that always points to magnetic north.

Parts of a baseplate compass

• Direction of travel arrow: Arrow on the baseplate pointing away from you; you follow this direction
• Rotating bezel: Ring with 0°–360° markings; you set your bearing here
• Orienting lines: Lines inside the housing that you align with map grid lines
• Magnetic needle: Always points to magnetic north; the red end points north

Taking a bearing from the map

1. Lay the compass on the map with the long edge connecting your current position to your destination
2. Rotate the bezel until the orienting lines align with the north-south grid lines on the map (north lines pointing to the top of the map)
3. Read the bearing at the direction-of-travel arrow — this is your bearing in degrees
4. Hold the compass level, turn your whole body until the magnetic needle aligns with the orienting arrow (red in red)
5. The direction-of-travel arrow now points toward your destination — follow it

Following a bearing in the field

Once you have your bearing set:

1. Pick a landmark in the direction the arrow is pointing (a tree, a building, a rock)
2. Walk to that landmark
3. Re-check your compass — the bearing is already set
4. Pick the next landmark in the same direction
5. Repeat — this is more accurate than staring at the compass while walking

---

Magnetic vs True North and Declination

Maps are drawn to true north (the geographic North Pole). A compass points to magnetic north (the magnetic North Pole), which is not in the same location and moves over time.

The difference between true north and magnetic north is called magnetic declination (or variation).

• East declination: The compass points east of true north; subtract the declination from your compass bearing to get a map bearing
• West declination: The compass points west of true north; add the declination to your compass bearing to get a map bearing

The declination for your area is marked on the margin of topographic maps and is available from your country's mapping agency. In some areas it is only 1–2°, which is negligible for practical navigation. In other areas (e.g., northern Canada) it can exceed 20°, which is significant.

Rule of thumb for approximate navigation: If declination is below 5°, ignore it for emergency navigation. If it is higher, adjust your bearing.

---

Grid References

Grid references allow you to communicate a precise location on a map to others.

Reading a grid reference (six-figure)

Maps have a grid of numbered squares. To give a 6-figure grid reference:

1. Find the vertical line to the LEFT of your point — this is the "easting" (eastward coordinate). Read the two-digit number at the bottom of the map for that line.
2. Estimate how many tenths of the square your point is to the right of that line (0–9). Add this digit.
3. Find the horizontal line BELOW your point — this is the "northing" (northward coordinate). Read the two-digit number at the side of the map for that line.
4. Estimate how many tenths of the square your point is above that line (0–9). Add this digit.

The six-figure grid reference is: [Easting two digits][Easting tenths][Northing two digits][Northing tenths]

Example: Grid reference 347 521 means 3.7 squares east, 5.1 squares north of the reference corner.

---

Reading Contour Lines

Contour lines are the curved lines on topographic maps that connect points of equal elevation.

What they show:

• Each line = a fixed elevation above sea level (the contour interval; usually 10m or 20m, noted in the map legend)
• Lines close together = steep terrain
• Lines far apart = gentle slope or flat terrain
• Lines forming a closed ring that gets smaller = a hill (summit at centre)
• Lines forming a "V" shape pointing uphill = a valley or drainage (water flows through V shapes)
• Lines forming a "V" shape pointing downhill = a ridge

Practical use in emergency navigation:

• Plan routes along valleys (gentler, but potential flood risk) or ridgelines (higher but exposed)
• Identify crossing points: where contour lines are furthest apart (gentle slope) for river and hill crossings
• Assess climb difficulty: count the number of contour lines you will cross on a route and multiply by the contour interval to get total elevation gain

---

Waterproofing Maps

A wet paper map becomes unreadable quickly. Protect your maps:

1. Lamination: The most durable protection; cannot be written on with most pens
2. Waterproof map case: Clear pouches that allow you to read and reference the map without removing it
3. Map sealer spray: Applied to paper maps; adds water resistance while preserving writability
4. Zip-lock bag: The emergency solution — not ideal, but better than nothing

Mark your intended route on the map before departure with a pencil or waterproof pen.

---

Planning a Route

1. Identify your start and end points on the map
2. Measure the direct distance using the scale
3. Identify obstacles on the direct route (hills, rivers, urban areas, known hazard zones)
4. Plan a route around or through obstacles, noting key waypoints (junctions, bridges, landmarks)
5. Calculate total distance and walking time for your group
6. Identify rest stop points (sheltered areas, water sources, elevated ground with visibility)
7. Write down the route as a list of bearings and distances between waypoints — this is your route card

---

Quick Reference

Situation	Action
GPS unavailable, need to navigate	Use oriented map and compass bearing to destination
Map not oriented to ground	Use compass to orient north edge of map to magnetic north
Need to communicate location to rescuers	Give 6-figure grid reference from your map
Unsure of bearing to destination	Place compass edge between current position and destination on map; rotate bezel to align north lines
Declination confusion	Check map margin for declination value; add or subtract as noted
Steep terrain ahead on planned route	Read contour lines — closely spaced means steep; choose a gentler route
Map getting wet	Place in zip-lock bag; trace route on a dry scrap of paper before it deteriorates
Landmark on map not visible in field	Move to higher ground for better visibility; recheck orientation
Separated from group without map	Follow a watercourse downstream; follow road signs; find high ground for orientation
Night navigation	Follow a memorised compass bearing to next waypoint; use a dim torch on the compass only