Create a map

Download data

First, you will download a .csv file that contains general information about the hospitals in Clark County, Nevada.

  1. Download the Clark County Hospitals .csv file to your computer and open it.

    You see a table with columns of longitude, latitude, cases, name, cost, and so on. This data comes from the Nevada Compare Care site and represents hospital charges in Clark County, Nevada, in 2015. It's hard to visualize where these hospitals are located or any patterns in the information. Making a map is a better way to understand your data than viewing it as a table, so that's your next task.

  2. Close the .csv file.

Add a data layer to a new map and start visualizing patterns

Layers are the way geographic data is organized and combined to create maps. For example, a map may consist of a roads layer, a lakes layer, and buildings layer. These layers are also the basis for geographic analysis to aid in decision making. You will create a map layer by adding your .csv file to an empty map.

  1. Sign in to your ArcGIS organizational account or into ArcGIS Enterprise using a named user account.

    If you don't have an organizational account, you can sign up for an ArcGIS free trial.

  2. On the ribbon, click the Map tab.

    Depending on your organizational and user settings, you may have opened Map Viewer Classic. ArcGIS Online offers two map viewers for viewing, using, and creating maps. For more information on the map viewers available and which to use, please see this FAQ.

    This tutorial uses Map Viewer.

  3. In Map Viewer, in the Layers pane, click the arrow next to the Add button and click Add layer from file.

    Add layer from file


    If you are using an ArcGIS Enterprise account, click Add layer instead. Click My Content and choose ArcGIS Online. Search for and add the Clark County Hospitals layer owned by ArcGISOnlineExercises. Skip to step 10.

    The Add Layer window appears.

    Add Layer window

  4. Drag the Clark_County_Hospitals.csv file to the Add Layer window.

    Alternatively, click Your device and browse to the .csv file.

  5. For How would you like to add this file, choose Upload the file as an item and add it to the map. Click Next.

    A list of fields appears. Map layers consist of spatial and tabular information. The table will contain the same columns—also called fields or attributes—as the .csv file.

    Fields list

  6. Click Next.

    The Location settings page appears. Spatial information for the layer will be derived from the Latitude and Longitude columns in the .csv file.


    If your table contains the names or addresses of locations instead of latitude and longitude fields, try this tutorial about geocoding data: Convert a list of historic places into a map.

  7. Click Next.
  8. For Title, type Clark County Hospitals.
  9. Click Create and add to map.

    The new layer appears on the map

    Data visualized on the map

    The map displays the locations of the hospitals listed in the .csv file. Each hospital is considered a feature in the layer. You also have access to the descriptive information, or attributes of the data, by viewing pop-ups for features on the map.

  10. On the map, click any circle.

    A pop-up window appears with information about the hospital from the layer's table.

    Pop-up with information for Summerlin Hospital

  11. Close the pop-up.

Change the basemap and layer style

Maps in ArcGIS Online consist of layers. You added the Clark County Hospitals layer, but the map also has a basemap layer by default. Next, you'll change the basemap layer and the style of the feature layer.

  1. On the Contents (dark) toolbar, click Basemap.

    Basemap pane

    The Basemap pane appears. The Topographic basemap is selected. This basemap looks good but is better suited for a reference map than a thematic map. You'll choose a simpler basemap so it does not distract from the hospital data.

  2. In the Basemap pane, click Light Gray Canvas.

    You may see different basemaps depending on the configuration of your organization. If the Light Gray Canvas basemap is not available, skip to the next step without changing the basemap.

    Map with the Light Gray Canvas basemap

    Next, you'll configure the map's symbols so they are sized based on the number of cases at each hospital.

  3. On the Settings (light) toolbar, click Styles.

    Styles pane


    If the Settings toolbar is unavailable, on the Contents toolbar, click Layers. In the Layers pane, click Clark County Hospitals to select the layer.

    The Styles pane appears. Currently, the style is based on the data's location only. You'll configure the symbols to convey both location and one of the data's attributes.

  4. In the Styles pane, click the Field button. In the Add fields menu, choose Total cases in 2015 and click Add.

    Add fields menu

    The options under Pick a style update to reflect choices that are suitable for the Total cases in 2015 field. Counts and Amounts (size) is selected and the map updates to reflect this style. This style reveals some new patterns in the data. The larger the circle, the more patients that hospital admitted in 2015.

  5. On the Counts and Amounts (Size) card, click Style options.

    Style options button

  6. In the Counts and Amounts (size) pane, click Symbol style.

    Symbol style

    The Symbol style window appears. You'll adjust the symbol's properties so circles can be seen even when they are overlapping.

  7. Set Fill transparency to 25. Set Outline transparency to 0.

    Transparency settings

    The symbols on the map update. It is now easier to see overlapping circles.

    Map with overlapping symbols

  8. Click Fill color. In the Select color window, for Hex, type 0070FF.

    The color of the map symbols changes to blue.

    Symbol color set to blue

  9. Click Done three times: on the Select color window, the Counts and Amounts (size) pane, and the Styles pane.

Configure pop-ups and view a table

The pop-up that you viewed earlier displayed all the attributes for the features, which may be unnecessary for your map. You can configure pop-ups to only show those attributes that are important to your map. In this example, you only want to show the name of the hospital and the number of total cases.

  1. On the Settings toolbar, click Pop-ups.

    The Pop-ups pane appears and a sample pop-up appears on the map. The pop-up's title contains the name of the layer and the name of the hospital. This title is unnecessary for your map, so you'll remove it.

  2. In the Pop-ups pane, click Title. Erase the text in the box.

    Blank Title field in the Pop-ups pane

    The title text disappears from the sample pop-up. You'll replace the list of fields with a sentence that includes the relevant information.

  3. Next to Fields list, click the Options button. Click Delete.

    Options and Delete buttons

  4. Click Add content and click Text.
  5. In the text editing window, type {. In the menu that appears, click Name.

    Bracket and Name field

  6. After {Name}, type admitted {Total_cases_in_2015} patients in 2015.

    You can add fields by typing their names inside of curly brackets or by choosing them from the list that appears when you type a curly bracket.

  7. Use the Bold button on the toolbar to add bold formatting to {Name} and {Total_cases_in_2015}.

    Bold button

  8. Click OK.

    The sample pop-up replaces the field names with the attribute values for the selected feature.

    Final pop-up

    All the fields still exist in the data table, but they don't display in the pop-up. You can modify the contents of the pop-up at any time. You can still see all the attributes by showing the table.

  9. Close the Pop-ups pane.
  10. In the Layers pane, next to Clark County Hospitals, click the Options button. Click Show table.

    Options and Show table buttons

    The layer's table appears below the map.

  11. Review the data in the table. Close the table when you are finished.

Save the map and update the item details

Your map now tells a story about the location and size of hospitals in Clark County. For example, the hospital with the largest caseload in 2015 is located in Winchester, an unincorporated township that contains the Las Vegas strip. The hospital with the smallest caseload is in Boulder City about 26 miles away. You assume these size differences reflect relative population density in those places, but you'll want to add some demographic data to your map to verify that. For now, you'll save your map so you can share it with your editor when you present your story.

  1. On the Contents toolbar, click Save and open and click Save as.

    Save and open menu

  2. In the Save Map window, for Title, type Hospitals in Clark County, Nevada. Click Save.

    By saving your map, you also created a corresponding item page that contains information, actions, options, and settings for the map.

  3. On the Contents toolbar, click Map properties. In the Map Properties pane, click Item details.

    Item details link in the Map Properties pane

    Your map's item page opens in a new window. The item details are missing important attribution and descriptive information that you should fill in before you share the map. For example, you should give credit to the data providers.

  4. Scroll to the bottom of the page. Next to Credits (Attribution), click Edit.
  5. Type Nevada Department of Health and Human Services, Center for Health Information Analysis (CHIA). Click Save.
  6. Close the item page.

Share the map

Eventually you'll want to share the map with your editor as part of your presentation, but it's not quite ready for that yet. You need to do some more work on it until a newsworthy story emerges. In the meantime, you want to share the map with your intern and one of your colleagues so that they can see what you've done so far and provide feedback on what to explore next.

The fastest way to share a map is to share it with everyone and send an email that includes a link to your map. In the future, you could also embed the map in your newspaper's website and create a web app including an ArcGIS StoryMaps story with additional text, videos, images, and web pages to enhance your map.

  1. In Map Viewer, on the Contents toolbar, click Share map.
  2. In the Share window, choose Everyone (public) and click Save.

    Share window

    The Update sharing window appears. You must set the sharing level for the layer as well as the map.

  3. In the Update sharing window, click Update.
  4. Copy the link to the map so you can paste it into an email to share with others.

Your intern was right. With a .csv file of hospital data, you created a web map and have ideas to share and explore for your story about hospitals in Clark County. What's next? You can explore ArcGIS Online on your own to discover what else is possible.

You can find more tutorials in the tutorial gallery.