Density maps show the spread and concentration of values within a geographic area. Instead of individual points or symbols, the marks blend together, showing intensity in areas with a high concentration. You can control color, size, and intensity.

Let's say you want to understand the geographic concentration of orders. You might create a density map using the following steps:

1. Navigate to the Density of Orders sheet.
2. Double-click the Postal Code field in the data pane. Just as before, Tableau automatically creates a symbol map geographic visualization using the Latitude (generated), Longitude (generated), and State fields.
3. Using the drop-down menu on the Marks card, change the mark type to Density. The individual circles now blend together showing concentrations:

Try experimenting with the Color and Size options. Clicking on Color, for example, reveals some options specific to the Density mark type:

Several color palettes are available that work well for density marks (the default ones work well with light color backgrounds, but there are others designed to work with dark color backgrounds). The Intensity slider allows you to determine how intense the marks should be drawn based on concentrations.

This density map displays a high concentration of orders from the East Coast. Sometimes, you'll see patterns that merely reflect population density—in which case, your analysis may not be particularly meaningful. In this case, the concentration on the East Coast compared to the lack of density on the west coast is intriguing.