Why Maps Still Matter When GPS Does Most of the Work — Terrain, Routes & Battlefield Reading // Log 003

GPS is very good at telling you where you are. A map is better at telling you what the ground is going to do to you.

I served 24 years in the British Army, including infantry, Recce Platoon and CIS/communications roles. Those jobs made me look at the same landscape in different ways: first as ground to move through and observe, then as ground that helps or blocks communications. That is why I am much more interested in what a map explains than in the fact that it can produce a grid reference.

A grid reference is an answer to one question

A coordinate answers where? It does not automatically answer:

• how steep the approach is;
• what can be seen from the position;
• what remains hidden in dead ground;
• whether a vehicle can reach it;
• which route is fastest rather than shortest;
• where water, walls, woods or buildings create obstacles;
• whether two radios are likely to have line of sight;
• what the place meant in a historical battle.

Those questions are why maps remain useful even when a digital device can place a blue dot on the screen almost instantly.

Contours: the lines that turn paper into ground

Contour lines connect points of equal elevation. Close contours indicate steeper ground; wider spacing generally indicates gentler slopes. Their shape reveals spurs, re-entrants, ridges, valleys and saddles.

That sounds elementary until you have to make a route choice at night, under load, or while deciding where an observer, headquarters or rebroadcast station might work.

A route that is two kilometres shorter can be slower if it crosses repeated steep features. A position that appears dominant can have a blind reverse slope. A shallow re-entrant can hide movement from a position only a short distance away.

Dead ground: what the observer cannot see

Dead ground is terrain hidden from an observer by the shape of the land or another obstacle. It is one of the most important things a flat digital route can fail to communicate intuitively.

For reconnaissance, dead ground offers both opportunity and risk. It can conceal your movement. It can also conceal somebody else’s.

Military history repeatedly turns on the same principle. Wellington used the reverse slope at Waterloo to reduce exposure to French artillery and observation. On the Somme, small folds in the chalk landscape affected fields of fire and approaches to trenches. In the Falklands, rocky ridges and bowls repeatedly hid positions until troops were very close.

A route is not a line

When I look at a route, I want to know more than distance:

• Surface: road, track, peat, rock, mud, sand, woodland?
• Gradient: what is the total climb and descent?
• Load: what are people and vehicles actually carrying?
• Exposure: where can the route be observed?
• Obstacles: bridges, walls, rivers, minefields, narrow streets?
• Alternatives: what happens if the first route is blocked?
• Time: when does darkness, weather or enemy action change the answer?

The shortest route and the best route are often different things.

Recce: proving what the map cannot

A map is a model of the ground. Reconnaissance tests that model.

The track marked on the sheet may be washed out. The bridge may not carry the vehicle weight you need. A wood may be thicker than expected. A wall, construction site or flooded ditch may have appeared since the mapping was produced.

That is why recce is not simply “go and have a look”. It should answer specific questions for the people who have to act afterwards. Can the route carry the force? Can the position observe the objective? Can it be resupplied? Is there enough space? What is the fallback?

CIS: the landscape becomes a radio problem

Later in my career, working in communications and information systems, the same hills created a different set of questions.

A radio path depends on more than distance. Frequency, antenna height, power, terrain, buildings and atmospheric conditions all affect performance. High ground can improve line of sight. Put a ridge between two stations and the same distance may become a much harder link.

A rebroadcast or relay position therefore has to be more than high. It must be reachable, supportable, secure enough for the task and actually improve the network geometry.

This is one reason I dislike planning overlays that treat communications icons as if equipment appears by magic. Somebody has to get the people, batteries, generators, antennas and vehicle onto that ground and keep them there.

GPS: excellent tool, bad substitute for understanding

None of this is an argument against GPS. Satellite navigation is an extraordinary capability. It reduces navigation error, speeds reporting and integrates with digital mapping in ways an older paper-only system could not.

The danger is not the tool. It is allowing a precise coordinate to create false confidence.

You can know your position to within metres and still choose the wrong route, sit in dead ground, put a radio behind a masking ridge or misunderstand why an enemy position dominates the approach.

Paper maps still have advantages

A full paper sheet lets you see a wider area at once without repeated zooming and panning. It is easy to mark, compare routes and build a shared visual picture around a table.

It also does not depend on a battery. That does not make paper indestructible — rain, wind and damage are real — but redundancy matters. Good navigation is rarely about choosing one technology and rejecting the other.

Historical maps need source criticism too

A battlefield map is not neutral just because it is old.

Ask who produced it, when, for what purpose and using what information. A contemporary staff map may show what a headquarters believed, not what actually existed. A post-war map may simplify disputed movements. A modern tourist map may prioritise readability over tactical detail.

The best Field Notes maps therefore sit beside text, primary accounts and other mapping rather than being treated as absolute truth.

Case study: the Somme

The Battle of the Somme is often imagined as one enormous flat field. A map immediately breaks that myth. The Ancre valley, Thiepval ridge, villages, woods, chalk slopes and sunken roads created different tactical problems along the front.

A first-day attack map shows where divisions were meant to move. The contour and trench information explains why identical-looking arrows produced very different outcomes.

Read Log 007 — Battle of the Somme: Complete Field Guide →

Case study: the Falklands

The Falklands campaign is another excellent demonstration. The island is not huge, yet the movement from San Carlos to Stanley became a major logistics and endurance problem because of peat, sparse roads, lost helicopter lift and the need to move artillery and ammunition forward.

Read Log 004 — Why the Map Lies About Distance →

Coordinates on a T-shirt: when they mean something

Gallus uses coordinates most effectively when the exact place is part of the story. The point is not to make a design look “technical”. It is to anchor the wearer to real ground.

A battlefield coordinate should encourage the next question: what happened there, and why did that position matter?

Wear the geography

• Falkland Islands 1982 Map T-Shirt
• Operation HERRICK Helmand Province Map T-Shirt
• Basra 2003 Operation TELIC Map T-Shirt

Sources & further reading

• Ordnance Survey — relief and contour lines
• Ordnance Survey — map-reading guide
• National Army Museum — Battle of the Somme
• National Army Museum — British Army and the Falklands War

I use maps here as evidence and explanation, not decoration. Where a historical map is interpretive or reconstructed, I identify the source so the reader can distinguish contemporary information from later analysis.