- Video length: 1:42
- This video was created with ArcGIS Pro 2.0.
Symbology is the use of symbols to represent the features and attributes of a map layer. For example, in a layer of cities, black circles might symbolize the cities. The size of the circles might be varied to symbolize each city's population. Symbols are defined by visual properties like shape, size, color, spacing, and (in 3D) perspective height. The choice of symbols is a central part of map design.
- Estimated time: 30 minutes
- Software requirements: ArcGIS Pro
The tutorial steps in the online help reflect the look and capabilities of the current software release. If you have an earlier software version, use the offline help system to open the tutorial. To switch from the online to the offline help system, see About ArcGIS Pro Help. If you don't have ArcGIS Pro or ArcGIS Online, you can sign up for an ArcGIS free trial .
Open the project
In this project, you'll make a map of bus routes, bus stops, and population density in Christchurch, New Zealand.
- Start ArcGIS Pro and sign in if necessary.
- On the start page, under your recent projects, click Open another project.
If you already have a project open, click the Project tab on the ribbon. In the list of tabs on the left, click Open.
- On the Open project page, click Portal and click Browse .
- On the Open Project dialog box, under Portal , click All Portal .
- At the top of the dialog box, in the Search box, type Symbolize map layers tutorial and press Enter.
- In the list of search results, click Symbolize map layers to select the project package.
If there is more than one project package with this name, make sure to select the correct one. In the upper right corner of the Open Project dialog box, click the Show/hide details panel button . The owner should be ArcGISProTutorials.
- Click OK.
The project opens with a map view of New Zealand. You'll zoom in to the study area of Christchurch. With a population of 381,800, Christchurch is the third-largest city in New Zealand.
The project is stored in your <user documents>\ArcGIS\Packages folder.
- On the ribbon, click the Map tab if necessary. In the Navigate group, click Bookmarks and click Christchurch Urban Area.
The Urban Area layer has been symbolized by default with a light-green fill color and a black outline.
Symbolize the urban area
The purpose of the Urban Area layer is to define the study area boundary. The solid fill obscures the basemap. You'll change the symbol to make the interior area hollow.
- In the Contents pane, click the Urban Area layer to select it.
The layer is highlighted in the Contents pane. On the ribbon, the Feature Layer contextual tab appears.
- On the ribbon, under Feature Layer, click the Appearance tab. In the Drawing group, click Symbology .
The Symbology button is a split button. Click the top half of the button (the icon) unless you are instructed to click the bottom half (the drop-down menu).
The Symbology pane opens. The symbology method is Single Symbol, which means that all features in the layer are drawn with the same symbol. In this case, the layer only has one feature.
- In the Symbology pane, click the symbol.
The pane heading changes to Format Polygon Symbol. Here you can choose a different symbol from the gallery or change the properties of the current symbol.
You can open this pane directly by clicking the layer's symbol in the Contents pane.
- Under Format Polygon Symbol, click the Properties tab.
Under Properties, the Symbol tab is selected. You can now change basic properties of the symbol.
- Click the Color drop-down arrow. On the color palette, choose No Color.
- Click the Outline color drop-down arrow. On the color palette, choose Gray 70%.
When you hover over a color square, its name appears.
- In the Outline width box, change the width to 2 pt and press Enter.
The symbol properties are previewed in the window at the bottom of the pane.
- Click Apply to update the map and the Contents pane.
On the map, the urban area boundary is sharply defined and the basemap is visible inside it. Now you'll display the bus stops and bus routes.
- In the Contents pane, select the check boxes next to the Bus Stops and Bus Routes layers to turn them on.
You'll change the default symbology for both layers. You'll also choose a more neutral basemap.
- On the ribbon, click the Map tab. In the Layer group, click Basemap and choose Light Gray Canvas.
Before continuing, you'll save your changes.
- On the Quick Access Toolbar, click the Save button to save the project.
Symbolize the bus stops
The current symbol for the Bus Stops layer is a small circle. You'll replace it with a symbol that represents bus stops more appropriately.
- In the Contents pane, click the Bus Stops layer to select it.
- In the Symbology pane, under the Bus Stops heading, click the symbol.
The pane heading changes to Format Point Symbol.
If you need to open the Symbology pane, right-click the Bus Stops layer in the Contents pane and click Symbology .
- Under Format Point Symbol, click the Gallery tab.
- In the search box, type bus and press Enter.
Your search results may be different from those in the image, but they should include bus station symbols. (The symbol is called Bus Station, but it is suitable for bus stops.)
- Click the smallest bus station symbol to select it.
The map and Contents pane update with the new symbol. After choosing a symbol from the gallery, you can modify its properties.
- In the Symbology pane, under Format Point Symbol, click the Properties tab.
- Click the Color drop-down arrow. On the color palette, choose Cabernet (last row, last column).
- Change the size to 8 pt and press Enter. Click Apply.
- At the bottom of the Symbology pane, under the preview window, change the magnification setting to 400%.
The preview window shows that the Cabernet color is applied to the bus icon but not to the gray symbol outline. This is because the symbol has more than one layer.
- At the top of the Symbology pane, under the Properties tab, click the Layers tab .
The Bus Station symbol has two symbol layers: the bus icon and a white circle with a gray outline.
- Click the white circle to select this symbol layer.
Underneath the selected symbol layer, there are options for changing the symbol layer's properties.
- Click the Outline color drop-down arrow and choose Cabernet.
In the preview window, the bus icon and the symbol outline are the same color.
- At the bottom of the Symbology pane, click Apply.
At the present map scale, the bus stop symbols clutter the map. You'll set a visibility range on the layer so the symbols appear only when the map is zoomed in to a specific scale.
- In the Contents pane, select the Bus Stops layer if necessary.
- On the ribbon, under Feature Layer, click the Appearance tab. In the Visibility Range group, click the drop-down menu next to Out Beyond and click 1:24,000.
The symbols disappear from the map. In the Contents pane, the layer's check mark is gray. This means that the layer is turned on but not visible at the current map scale.
- In the lower left corner of the map view, click the map scale drop-down menu and click 1:24,000.
The map zooms in and the bus stops display.
- On the ribbon, click the Map tab. In the Navigate group, click the Previous Extent button to return to the full urban area.
Symbolize the bus routes
The bus routes are currently drawn with a single symbol. The attribute table for the layer contains route names, route directions, and route types that can be used to symbolize the features in different ways.
- In the Contents pane, click the Bus Routes layer to select it.
- On the ribbon, under Feature Layer, click the Data tab. In the Table group, click Attribute Table .
The attribute table opens. You'll symbolize the routes according to their values in the Type field.
- Scroll down through the table and look at the values in the Type field.
There are four route types:
- City connectors connect suburbs to the city.
- Suburban links connect suburbs to each other.
- Metro lines follow major roads.
- Ferries connect the suburb of Lyttelton to Diamond Harbour.
You'll represent each route type with a different color.
- Close the Bus Routes attribute table.
- In the Symbology pane, under Bus Routes, click the Symbology drop-down menu and choose Unique Values.
- Under Value field, click the Field 1 drop-down menu and click Type.
Now that you have specified the attribute to symbolize, the bottom portion of the pane shows an entry for each of the four route types. It also shows a fifth entry for all other values.
- Click the Color scheme drop-down arrow. At the bottom of the list of color schemes, select the Show names check box.
You can also hover over a color scheme to see its name.
- Choose the Set 1 (5 classes) color scheme.
Because there are only four unique values for this attribute, the <all other values> symbol isn't needed.
- In the Symbology pane, under Color scheme, click the More drop-down menu and clear the Show all other values check box.
On the map, each type of route has a different color. You are still free to modify the symbol properties. You'll change the Ferry symbol because ferry routes are conventionally symbolized with dashed lines.
- In the Symbology pane, click the line symbol for Ferry.
- Under Format Line Symbol, click the Gallery tab. In the list of symbols, click Ferry.
The symbol updates in the Contents pane and on the map.
Finally, you'll symbolize the population in the Christchurch urban area to visualize the relationship between bus routes and population.
- In the Contents pane, select the Population check box to turn on the layer.
A dense layer of points covers the urban area. Each point is the center of a meshblock. A meshblock, like a United States census block, is a small area for which census data is collected. In this layer, each point stores the population of its meshblock.
- On the map, click a population point.
A pop-up shows the 2013 population for the meshblock associated with the point. By drawing the layer as a heat map, you'll be able to see where population is concentrated.
- Close the pop-up window.
- In the Contents pane, click the Population layer to select it.
- In the Symbology pane, click the Symbology drop-down menu and click Heat Map.
The heat map displays. At the moment, it represents the density of the point locations, not their population values.
- In the Symbology pane, click the Weight field drop-down menu and click Pop 2013.
Now the heat map represents the population density.
- Click the Color scheme drop-down arrow and click Heat Map: Dark Blue-Cyan.
The most sparsely populated areas are dark blue and the most densely populated areas are cyan. The heat map covers the bus routes, so you'll change the order of layers in the Contents pane.
- In the Contents pane, drag the Population layer beneath the Urban Area layer. Confirm that the Population layer is still selected in the Contents pane.
- On the ribbon, under Feature Layer, click the Appearance tab. In the Effects group, move the Layer Transparency slider to 75%.
The bus routes correspond well to the densely populated parts of the urban area.
- On the Quick Access Toolbar, click the Save button .
- Close any open panes other than the Contents and Catalog panes.
In this tutorial, you used methods such as Single Symbol, Unique Values, and Heat Map to symbolize map layers. You worked with symbol drawing layers to modify the bus stop symbol. You used attribute values to set symbology for the Bus Routes and Population layers. You also applied visibility ranges and transparency to layers.
There are more symbology methods to explore and many ways to modify and design symbols for your maps—a few resources are listed in the Related topics below. To be inspired by examples of maps designed with ArcGIS Pro and other ArcGIS applications, visit the Maps We Love site.