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precisely located and more accurate in elevation, the Trigonometric
Points are marked by a plate, fixed permanently on the ground.
The main characteristics of contour lines are:
1. They connect point of equal elevation.

2. Contour lines always connects close contour lines. This is not
always visible on the map.
3. They never cross, split or intersect – at a cliff they might

merge.
4. Evenly spaced contour lines indicate a uniform slope.
5. Closely spaced contour lines show a steep slope.
6. Widely spaced contour lines show gentle slope.

7. Closed contours with arrow in the centre represent depressions.

Figure 4. 9. Slopes

The representation of cliffs and rocks on topographic maps is a

very difficult task still yet, even in the realm of digital cartography:
the painting of rock hills is mostly “hand-made”. Furthermore, this
expensive method can only be produced by specialists: the painter has

to use graphical tricks to give steep rocks depicted on a map
equivalent visual importance, compared to that observed in nature.
During the last two centuries, cartographers have developed different
cliff representation styles.

1. What are contour lines? What do they represent?
2. What do you know about a contour interval, or equidistance?
3. How are cliffs and rocks represented on topographic maps?

4. What do you know about digital cartography?
5. Is it easy to represent cliffs and rocks on topographical maps?

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