Page History

...

Now that you know the geographic coordinate system of the County feature class, you will need to define it, so that ArcGIS knows, as well. Please note that the geographic coordinate system and projection must be defined based on metadata provided from the data source itself. If you cannot locate such metadata, you should contact the provider of the data for such the information. You cannot simply guess or decide which projection to use when defining the data (though, occasionally, you may have to resort to educated guesses and trial-and-error when metadata absolutely cannot be tracked down from the data provider.)

1. On the ribbon, click the Analysis tab.
2. In the Geoprocessing group, click the Tools button to open the Geoprocessing pane on the right.
3. In the 'Find Tools' search bar, type "define projection".
4. Click the Define Projection tool to open it.
5. Use the ‘Input Dataset or Feature Class’ drop-down menu to select County.
6. For the 'Coordinate System', click the Select coordinate system button to the right of the drop-down menu, click the Select coordinate system button.
7. In the Coordinate System window, expand Geographic coordinate system > North America > USA and territories.
8. Click NAD 1983 and click click OK.
9. Ensure your Geoprocessing pane appears as shown below and click Run at the bottom of the Geoprocessing pane.

...

1. At the top of the Geoprocessing pane, click the Back arrow.
2. In the Find Tools search bar, type ‘project’project’.
3. Click the Project tool.
4. For 'Input Dataset or Feature Class', use the drop-down menu to select the County layer.

...