ArcMap Tutorial Creating a New Polygon Shapefile

Begin at the end of the GeoReferencing tutorial — either continue from there or open the .mxd file with georeferenced map. In the right column is the interface for ArcCatalog, which you can access by clicking the toolbar button at the top of the screen (under the Windows menu) with the yellow cabinet.

In ArcCatalog, right-click on the folder you want the new shape file to live in and select New>>Shapefile. This dialog window will appear. Give it a concise, descriptive name and select Polygon (rather than line or point). You need not set a coordinate system yet, so click OK.

A new shape file should appear in the Table of Contents. Nothing shows up in the Data View yet, as you have not yet created any polygons.

Zoom into a color-coded area.

Open the Editor Toolbar by clicking the button with the pencil and set of dots on it under the Customize menu.

On the Editor toolbar, choose Start Editing from the drop down menu. When this window appears, choose the shape file you just created.

When you start editing, a Create Feature sidebar appears on the right. Double-click on your new shape file and select polygon. Feel free to add a bit of metadata and hit OK.

Now, you will start by clicking on one of the corners of the C1 neighborhood and single click your way around the polygon until the last corner, at which point you double-click.

When a polygon is completed, it fills with a color and its outline becomes turquoise.

If you make any errors or want to clean up your work, you can select the pointer on the Editor toolbar and double-click on any polygon and the vertices will be individually editable. You can select a vertex and drag it into a more accurate location. Accuracy is key in this assignment.

Here I can zoom in and drag one of the vertices into a better position.

Now you can see the single polygon in the context of the whole map. On the Editor toolbar, select Save Edits — SAVE OFTEN — and stop editing (you can see the toolbar is no longer activate).

Now you must add an identifying field to the attribute table. Right click on your layer in the Table of Contents and Open Attribute Table. In the upper left of the window for the attribute table, choose the drop down, then select Add a Field. This field will be called AreaNumber, and it is a Text field with length 4.

You can see that the field is added here.

Now you must return to the Editor toolbar and Start Editing — you can see the toolbar buttons are enabled. Open the Attribute Table and enter the area designation (C1 in this case), then save your edits.

Continue this process creating polygons for all of the neighborhoods and SAVE YOUR EDITS AND YOUR .MXD FILE OFTEN. When you finish the assignment, you will turn in the .mxd and the shape file.