Images found in ancient petroglyphs - pictures scratched, carved or pecked into rocks - have become emblematic of the Southwest.
You can get a closer look at petroglyphs at two sites near Yuma. And because pioneer routes followed ancient trails, you may also find messages from more recent passersby, from Spanish explorers to otherwise unknown Forty-Niners.
The closer site is at Antelope Hill, a 575-foot knob of sandstone east of Wellton, where "desert varnish," the dark patina that forms on rock in arid conditions, provides the canvas for mostly human figures. Experts believe that Antelope Hill was the West's largest milling quarry, a neutral site where many tribes found sandstone to shape into grinding tools. The images probably served both religious and artistic purposes -- and as communication among tribes.
Directions: Take I-8 east to exit 37 and follow Antelope Hill Road. Just before metal bridge (Gila River), turn right. More info: BLM Yuma office, 928.317.3200.
Farther east, the Painted Rock petroglyph site just outside Gila Bend is the largest of about 40 in the immediate area, and includes about 800 images on basalt boulders overlaying a granite outcrop. Images here include the concentric spirals often found at Hohokam sites, pictures of mounted riders that were made after the Spanish introduced horses to the region, and pioneer grafitti.
Directions: East on I-8 about 100 miles to exit 102, Painted Rock Dam Road. Follow Painted Rock Dam Road north 10.7 miles to Rocky Point Road, then left (west) about 0.6 miles to the site. More info: Phoenix BLM, 623.580.5500.
Since Arizona is home to the world's largest gathering of gem and mineral dealers (Tucson hosts 40+ shows January to mid-February) and a huge outdoor "rock swap" (Quartzsite, January), the state's best rockhounding is probably done with a wallet instead of a shovel.
But if you're interested in the "do it yourself" approach, you can collect "reasonable amounts" of minerals, rocks and gems on most Bureau of Land Management property -- for personal use only, not for sale or barter.
Start by checking land ownership at the local BLM office. If you can point to a location on a BLM topographical map, they can determine if the site is on public lands and open for rockhounding.
More info: Bureau of Land Management, 928.317.3200.