MELBA, Idaho — Taking a left onto Map Rock Road south of Nampa, I realized I was following modern road signs to find a set of ancient road signs: petroglyphs, which are intricate carvings found up and down the Snake River canyon outside of Boise. They are often located on the flat faces of boulders left where prehistoric Lake Bonneville once was. The petroglyphs, created by ancient indigenous people, are most often outlines and stickfigures etched into car-sized boulders. Th