APM: 21 Location: SR 115 and SR 78, Imperial Cty After the 78 split, we’re 18 miles from Interstate 8. APM: 17 Location: SR 115 and Keystone Rd, Imperial Cty We’ll approach a series of signed county roads as we head south. Turn left or right for CR S27/Keystone. APM: 12 Location: SR 115 and … Continue reading California State Route 115, SR 78 to I-8