There is a difference in the use of symbols, depending on the scale and style of the map. On small-scale maps, cities are usually shown by circles and dots; on large-scale maps by their streets. Medium-scale maps can fall somewhere in between and offer an opportunity to express the map’s unique style.
City point symbols
Ortelius’ built-in Styles & Symbols library contains a variety of city point symbols. Try placing them on your drawing canvas and adding labels to see how they would look on your map. When choosing symbols, remember a map reader can usually only distinguish beween a couple different symbols. Don’t get carried away using too many different kinds.
City symbols vary with the scale and style of the map. When choosing symbols, it is a common error to force large-scale symbols into small-scale maps and thus overburden them. In his classic 1948 text, General Cartography, Erwin Raisz provides guidance that can hardly be improved upon today.
“In the earliest maps, cities are shown by small, pictorial bird’s-eye views. Since the early walled cities were usually round, on small-scale maps their representation was either reduced to more or less circular layout of the wall or was symbolized by a circle. The circle as a city symbol survives up to the present time…” (p.97). “It was customary in early Renaissance maps to designate a city by a small pictorial group of houses. But since this group was very much larger than the size of the city, the exact location of the later was shown by a small circle within the group of houses. In small-scale maps the group of houses was omitted, and only the circle remained.” Today we still use circles, or several concentric circles, whose size and complexity indicate the relative size, population, or importance of the city.
On medium-scale maps where the general extent of a city or town can be shown, it can be represented by crossed lines indicating a street system, even if the pattern does not follow the actual street pattern of the city. Alternatively, the general outline of the city can be represented by a solid or semi-opaque fill.
In Making Maps, Krygier and Wood discuss the role of map intent and simplification. City boundaries can be quite complex, and are required to be accurate for official boundary purposes. But for a small- or medium-scale map, simplified boundaries are less distracting and better. This supports Raisz’s example representing a city’s outline with solid, semi-opaque or patterned fills on medium scale maps, above.
Consider how you might simplify the representation of cities on your small- or medium-scale maps. Simplification can enhance visibility and reduce clutter. It’s ok, even welcomed, to have more simplified features than would be shown on larger-scale maps. Ask yourself:
How much can I simplify while keeping the feature recognizable?
When should representation of a city change from an area symbol to a point? Or should a group of points be transformed into a small area? This is referred to as “dimension change” and is useful when changing scale and removing detail from your map.
Krygier and Wood point out, “While changes in scale are the most common reason to change dimensions, map makers can also change dimensions of features to remove clutter and detail form a map to support its point” (p.169). It’s worth noting, when it comes to scale – it’s all relative.
It is also posible to effectively use both point and area city symbols to represent different sized features on the same map.
In her textbook, Principles of Map Design, Judith Tyner discusses the visual variables of cartographic symbols. In addition to representing cities as points or areas, there are “additional visual variables that permit differentiation of symbols by the characteristics and values they represent” (p.136). The shape of a symbols is its primary distinguishing characteristic to identify different kinds of objects. For example, circles for towns, stars for capitol cities, and the like.
Visual variables include form, size, hue, color value (lightness, color intensity (saturation), pattern, texture, and orientation, as shown in this figure from Tyner’s book. To a lesser extent, location, crispness, transparency, resolution, and perspective height are used, and these may add more artistic character to a map.
Modern example with a traditional feel
In his Route 66 Traveler’s Guide and Roadside Companion, Tom Snyder used Ortelius to create these symbols that represent cities and towns on his medium scale maps. Tom effectively uses scale, simplification, and dimension change with many of the visual variables discussed above.
The symbols are various sized circles with a crosshatch pattern inside. While the hatch pattern is consistent, the size of the circle varies relative to the size of the city or town. To provide visual interest, Tom varies the orientation of the hatch to more or less match the direction of the road along the route. To accomodate different scales, Tom provides map details, also cased within circles, for places of particular interest.
Pictorial symbols are often used for decorative maps. These, adapted from Heather Child’s book, Decorative Maps, are vectorized for import into Ortelius.
Ortelius includes a full suite of drawing tools that can be used to draw your own decorative symbols. It also imports SVG and vector PDF files if you need to import scalable graphic files.
Time to get creative
We’ve reviewed the role of scale, simplification, dimension change and texture on city map symbols, and seen an excellent modern example. Now it’s time to get creative with making your own medium-scale city symbols in Ortelius.
Here we offer some inspiration. For example, you can draw a basic graphic with many buildings within a square shape, then use that graphic as a pattern fill for your symbols. We made a black version and a white version. In other examples, we used some of Ortelius’ built-in hatch styles, and a fill style with opacity. Even a simple small back square can provide interesting results when you apply randomness settings to a pettern fill. Have fun playing with styles to create interesting city symbols.
Of course, when you’re satisfied with your results you can save them to your User Library for future reuse.
The Role of Typeface
A final note. In addition to symbology, your selection of typeface will greatly influence the look and feel of your map. For example, notice how Tom Snyder’s carefully chosen typefaces echo the Route 66 icon and imply a vintage time period. Be sure to consider the appearance of text on your map. Our tutorial, Best Mac Fonts for Cartography, provides guidance to choose a good typeface and tips to establish a schema for text labels with your map projects.
Child, Heather (1956). Decorative Maps. Studio Limited, London.
Krygier, John and Denis Wood (2005). Making Maps, A Visual Guide to Map Design for GIS. The Guilford Press, New York.
Raisz, Erwin (1948). General Cartography. McGraw-Hill Book Company, New York.
Snyder, Tom (2011). Route 66 Traveler’s Guide and Roadside Companion, 4th Edition. St. Martin’s Griffin, New York.
Tyner, Judith (2010). Principles of Map Design. The Guilford Press, New York.