We finally found Helvetia (hell-vee-sha) on the 3rd attempt. I would recommend taking Sahaurita Road to Santa Rita Road South and you'll find the cemetery easily. A couple miles further up the road you will find what's left of Helvetia townsite. Compared to other photos I've seen of this site with many adobe walls standing, the site has very little left to see except the adobe walls pictured above.
Helvetia was a copper town and got its post office in 1899. In 1911 the mines shut down due to a drop in copper prices. There was only a small population here at its height but when the post office was discontinued in 1921, that officially ended the town.

It's situated in the beautiful Santa Rita Mountains and the chance to see the last of Helvetia made the trips especially rewarding. You can see what it used to look like by watching the Paul Newman movie "Hombre" for it was filmed here in 1966.