Diamond Ventures' Stone House celebrates Arizona's colorful ranching and farming era. Pennington House, the original "stone house", is believed to be the oldest remaining house built by Anglo Americans in Arizona. Built in 1858 by pioneer Elias Green Pennington, it is listed on the National Register of Historic Places.

Pennington's father, Elijah, who served with General George Washington at Valley Forge, gave each of his eight sons "a rifle, a dog, a horse, a saddle, and $2,100 in silver" at age 21.

Elias headed to Arizona, claimed fertile land on the bank of the Santa Cruz River and chose a desolate piece of high ground about a half-mile north of today's border with Mexico to build his home. The house was built and fortified with stone for the family's safety.

Along with growing corn for his family's use, Elias, dubbed "Old Pennington" by those who knew him, provided hay for the horses of soldiers stationed in Tucson. Elias and a son were attacked and killed by Apaches in 1869.