A good place to start if you are doing the Shell Game Power Tail. The trail is mostly along Agua Caliente Road which is one of the longest, well maintained and little-used roads in Maricopa County. It's quite scenic too. If you do the complete run you will get a different view of one of the largest nuclear plants in the US and a large railroad car boneyard. You will also come close to a 1920's TB Sanatorium and the site of the 1851 Oatman Massacre. The Massacre has been the story behind a couple of Hollywood Westerns. Also near the South end are the Painted Rocks, a great place to see lots of Petroglyphs.
This cache is placed at the North end of the run in an attempt to assist finders to be more efficient in their efforts.
The Shell Game run is located almost entirely in Maricopa County. 95% of the run is accessible with any car. For the remaining 5%, that is, side roads off the main Agua Caliente Road it would be advisable to use a high clearance vehicle.
Also, Cell phone service is spotty so be sure and tell someone where you're going to be.
Good luck and have fun.