IE is namely comprised of Riverside and San Bernardino counties. Both county lines start east of Orange and LA counties and extend to the CA-AZ border. Commute times from Riverside (IE) to Irvine, for example, is about 40 minutes without traffic. If you live 'up the hill' in Apple Valley/Victorville/Hesperia (IE), you're looking at a 90 minute commute without traffic.