Key Idea: Topic 13.5 is the synthesis, evaluation and skills strand of Option G — it is about reading urban information accurately off maps and graphs and quoting it back with the right figures and units. It rests on one micro: 13.5.1 — urban geographic skills: maps and graphs: the two core skills are cartographic (reading a topographic or street map — a feature at a grid reference, a six-figure reference, a compass direction, a distance off the scale) and graphical (reading a value, a difference between peaks, or a trend with figures off an urban graph such as a congestion index, a land-value gradient or a density transect). This is an Option G topic, examined on Paper 1 — you answer only the options you studied (SL answers 2, HL answers 3, the same questions). Marks are awarded for precise, correctly-quoted figures with units, not for explanation — and these skills also feed the structured questions and the [10] extended-answer essay, where you must apply data you have read to a real urban argument.
🗺️ 13.5.1 — Reading urban maps: grid references, direction, scale
On a topographic or street map of a real city you read a feature at a grid reference, give a six-figure grid reference (square first, then tenths), state a compass direction between two places, and use the scale to estimate a distance in km. The golden rule is order: eastings first (read across), northings second (read up) — 'along the corridor, then up the stairs'. Each read is marked on its own, so the skill is speed with accuracy — spot the read, do it cleanly, quote the figure with its unit, move on.
The four core map reads — and the method
| Read | Method | Worked check |
|---|---|---|
| Feature at a grid reference | Find the easting column, then the northing row — read what is in that square | E19 N12 -> Riverside School |
| Six-figure grid reference | Find the four-figure square, then estimate tenths across (easting) and up (northing) | 4 across, 5 up in square 1911 -> 194115 |
| Compass direction A to B | Stand at A, face B — read N/NE/E/SE/S/SW/W/NW from the way you travel | port -> hospital, straight across -> east (E) |
| Distance A to B | Measure the straight line in cm, then multiply by the scale value | 4 cm at 1:50 000 -> 4 x 0.5 = 2 km |
Key terms — cartographic skills
- Grid reference — numbers locating a place: eastings (read across) first, then northings (read up).
- Four-figure grid reference — names a whole grid square (e.g. 1911).
- Six-figure grid reference — pins an exact point by splitting each square into tenths (e.g. 194115).
- Scale — the ratio of map to real distance: 1:50 000 means 1 cm = 0.5 km; 1:25 000 means 1 cm = 0.25 km.
- Compass direction (bearing) — N, NE, E, SE, S, SW, W, NW between two points; stand at the start and face the end.
- Topographic map — a map showing features (relief, roads, buildings) of an urban area, read using the grid and scale.
Tip: Read the easting (across) before the northing (up), and the square before the tenths. For a six-figure reference: find the four-figure square, then estimate how far across (easting tenths) and up (northing tenths) the point sits, and write the easting digits then the northing digits. Swapping the order is the single most common skills mistake.
📈 13.5.1 — Reading urban graphs: values, peaks, trends
Option G also gives urban graphs — a congestion index, a land-value gradient, a population-density transect, or a pollution time-series. The skill is always the same: read a value off the correct axis, calculate a difference between two points, or describe the trend with figures. A value alone is not enough — a graph read scores only when you quote the exact figure with its unit, or, for a difference, the subtraction of two peak values. A vague trend word ('goes up and down') scores nothing.
Read the y-axis first. Find the day on the x-axis, go up to the line, read the index across — then subtract two peaks for a difference or describe the trend with figures.
🔒 Interactive diagram
Explore the labelled diagram, charts and maps for this topic in study mode.
The three core graph reads — and the method
| Read | Method | Worked check |
|---|---|---|
| Read a value | Find the day/time on the x-axis, go up to the line/bar, read the y-axis value across | Thursday morning peak -> 66 |
| Calculate a difference | Read both peak values, then subtract the smaller from the larger | Fri evening 88 - Wed evening 69 = 19 |
| Describe a trend | Give the overall direction PLUS figures (the peak day and its value) | rises through the week, peaking Friday at 88 |
Key terms — graphical skills
- Time-series graph — a line/bar graph with time on the x-axis (e.g. a congestion index over a week).
- Value — the figure read off the y-axis for a given point on the x-axis (quote it with its unit).
- Peak — the highest point of a line/series; name the day/time it occurs and its value.
- Difference — one value subtracted from another (e.g. one peak minus another peak).
- Trend — the overall direction the data moves (rising, falling, fluctuating) — always backed with figures.
- Land-value / density gradient — how a value (land price, people per km²) changes with distance from the city centre.
Example: Lagos — a congestion index that spikes at rush hour because road growth lags far behind car ownership. Barcelona — pollution falling inside its 'superblocks' where through-traffic is removed. Singapore — a road-pricing graph showing traffic drop as the congestion charge rises. Reading any of these is the same skill as reading the Marisport figure above — find the axis, read the value, quote it with its unit.
✍️ IB-style questions
Using the Marisport congestion graph: (a) state the evening-peak congestion index on Thursday; (b) calculate the difference between the highest and the lowest evening peak in the week; (c) describe the trend in the evening peak from Monday to Friday.
🔒 Model answer plan
See the mark-by-mark plan — for / against / judgement, with marking guidance — in study mode.
Examine the usefulness of maps and graphs for understanding traffic congestion in a named city.
🔒 Model answer plan
See the mark-by-mark plan — for / against / judgement, with marking guidance — in study mode.
✅ Quick self-check
Tap each card to reveal the answer.
In what order is a grid reference read? Eastings first (read across), northings second (read up) — 'along the corridor, then up the stairs'. For a six-figure reference, find the square, then estimate tenths across and up.
How do you turn a map distance into kilometres? Use the scale. At 1:50 000, 1 cm = 0.5 km, so multiply the measured cm by 0.5. At 1:25 000, multiply by 0.25. (4 cm at 1:50 000 = 2 km.)
How do you read a compass direction from A to B? Stand at A and face B; read N/NE/E/SE/S/SW/W/NW from the way you must travel. Straight across to the right is east (E); directly below is south (S).
What does a graph read need to score? The exact value with its unit off the correct axis — or, for a difference, the subtraction of two peak values. A vague trend word alone scores nothing.
What does a top [10] essay using these skills need? Weigh what maps and graphs reveal against their limits, anchor it to a named city (Lagos, Singapore), use accurate skills terms, and judge that they describe but do not explain congestion.
🎯 Highest-yield exam reminders
Exam Tips
- Option G is on PAPER 1 — answer only the options you studied (SL does 2, HL does 3); the skills feed both the structured questions and the [10] essay.
- Order matters: eastings before northings, square before tenths (six-figure).
- Direction = stand at the start, face the end (N/NE/E...); scale 1:50 000 -> x 0.5 km per cm, 1:25 000 -> x 0.25.
- Graph: read the value, subtract two peaks for a difference, or describe the trend WITH figures — never a bare trend word.
- Every skills mark needs the EXACT figure WITH its unit (km, grid digits, the index value).
- On the [10] essay, use the data you read but go further — weigh what maps and graphs reveal against their limits and judge that they describe rather than explain.