Making a clip coverage

If your project results in a relatively small area of suitable sites, you may want to clip out a smaller area to display at a larger scale, either using a separate maplimits inset, or as your main map. In either case the cleanest way to make the map is to work with coverages clipped to the same area. To make a clip coverage of an rectangular area:

First, you'll need to identify the are you want to clip. One way is to use MEASURE WHERE in Arcplot to identify two corner points.
The simplest way to make a rectangular coverage with two know corner points is to use Arcedit. Start Arcedit and create a new coverage using tics from some other coverage that has about the same areal extent (it doesn't matter much how close), specify that you want to add a special "box" type of arc, specify that you want to type the coordinates in from the keyboard (the ones you wrote down from Arcplot), and add them (I've provided an example of a 500x500 box here):
```
create clipcov othercov 
ef arc 
arctype box 
coord keyboard
add
2,1000,1500
2,1500,2000
(press enter to exit)
q
```
Build polygon topology (BUILD CLIPCOV)
Now you can either clip coverages with it (remember to specify the line options if the coverage your clipping has arc topology), or use this clip coverage as the first coverage in an IDENTITY -- handy for use with the WATER coverage in our dataset.