Map Types: Physical, Political, and Thematic

Maps are classified by what they show: physical maps show natural features such as landforms and water, political maps show human boundaries such as countries and cities, thematic maps show the distribution of one topic such as population or rainfall, and relief maps show the shape of the land surface. In brief: choose the map type to match the question. To find out where a mountain range is, use a physical or relief map; to find out which country borders another, use a political map; to see how a single variable (for example, population density or climate) varies across space, use a thematic map.

No single map can show everything, so geographers use different types for different purposes. This guide describes physical, political, thematic and relief maps with their symbols and techniques, compares them in a table, works through an example of classifying data for a thematic map, outlines how map types developed and corrects common mistakes.

What are physical maps?

Physical maps show the natural features of Earth’s surface: mountains, plains, plateaus, rivers, lakes, seas and deserts. They typically use color tints for elevation (green for low ground, then yellow and brown for higher land, with white for the highest) and blue for water, and they may mark peaks with symbols and names. Physical maps are used to study the layout of landforms, drainage patterns and natural barriers. They usually include a few political features such as the names of countries, but these are not the main focus.

What are political maps?

Political maps show boundaries made by people: countries, states and provinces, with their capitals, major cities and sometimes roads. Each country or region is usually shown in a different color so that the borders can be seen clearly. They are used to find out which places belong to which state, and where capitals and cities are. Boundaries change over time through wars, treaties and independence, so political maps become outdated, and some boundaries are disputed, which different maps may show in different ways.

What are thematic maps?

Thematic maps show the spatial pattern of one topic (theme), such as population density, climate, vegetation, land use, income or disease. The base map is simplified so that the theme stands out. The main techniques are: choropleth maps (areas shaded in different colors by class, best for rates or densities), dot maps (one dot represents a number of items, showing distribution), proportional symbol maps (circles with an area proportional to a value), isoline maps (lines joining points of equal value, such as isotherms or isobars) and flow maps (arrows with a width showing the size of movements, such as migration or trade). Thematic maps need a clear title and key, because the meaning of the colors is not obvious.

What are relief maps?

Relief maps show the shape and height of the land. This can be done with contour lines (lines of equal height), with layer tints (colors for height bands), with hill shading (shadows that make slopes look three-dimensional) or with a physical three-dimensional model. They are used for planning routes, understanding drainage and judging slopes. A topographic map combines relief with other features, such as roads and buildings, and is described in a separate article.

Map types compared

Worked example: making a choropleth map

1. Data (hypothetical): population densities in five regions: A = 12, B = 45, C = 80, D = 150 and E = 260 people per km².
2. Why density, not total population? A choropleth map should use rates or densities, because totals depend on the size of each area, which would mislead.
3. Choose classes: use four classes that separate the groups in the data: 0–50, 51–100, 101–200 and over 200.
4. Assign the regions: A (12) and B (45) fall in class 1, C (80) in class 2, D (150) in class 3 and E (260) in class 4.
5. Choose colors: a single color from light to dark, so that darker means denser: light yellow for class 1, up to dark red for class 4.
6. Add the title and key: “Population density by region (people per km²)”, with the four classes in the key.

How did map types develop?

Early maps were mainly general-purpose and showed both natural and human features. Thematic mapping developed in the 17th and 18th centuries: Edmond Halley published a map of trade winds in 1686 and a map of magnetic variation in 1701. In the 19th century, John Snow’s map of cholera cases in London (1854), and Charles Dupin’s choropleth map of literacy in France (1826), showed the power of mapping a single theme. In the 20th century, national atlases and computer cartography expanded the range, and today GIS lets users make thematic maps of nearly any data.

Which mistakes are common?

Mistake 1: Mapping totals instead of rates on a choropleth map

Large areas appear more important. Use densities, percentages or per-capita values.

Mistake 2: Assuming a political map shows physical features

Political maps focus on boundaries, so use a physical map for landforms.

Mistake 3: Forgetting to read the title and key on a thematic map

The colors have no universal meaning and depend on the theme and classes chosen.

Mistake 4: Treating borders as permanent or undisputed

Boundaries change, and a map shows them as of its date and the view of its maker.