Fodor's Expert Review Uspallata Pass on Ruta Nacional 7

This route heads west on R13 and then RN7 (also known as the Panamerican Highway) and takes you straight into the mountains. You'll go from vineyards to barren hills until you reach the Potrerillos Valley, then head farther west on R7 into the heart of the Andes. This was a major Inca route, so keep your eyes peeled for Inca tambos. You'll pass the Puente del Inca ancient thermal springs and the ruins of a spa from the 1920s. This is the only route between Chile and Argentina for miles and miles, so if you're self-driving, be ready to share the road with cargo trucks.