The route into Argentina from San Pedro de Atacama crosses the Andes through Paso de Jama, a mountain pass at about 13,800 feet above sea level. It was first necessary for us to get stamped out of Chile which is done at their border control office located just outside of San Pedro, 160km from the border.
There is apparently no concern about what you might do in between for there is nothing but mountains from there until the Argentine border. When we arrived in San Pedro de Atacama, we were told that the road through Paso de Jama had been closed due to snow for the prior 2 or 3 weeks but had just been reopened. There are 3 bus companies that make the trip across the mountains so we started making the rounds to see which ones had service and when they would be leaving. We ended up leaving a day earlier than planned since we figured it was better than taking a chance on another closure.
This picture shows one section of the road that was responsible for the closure.
A big portion of the trip was on what appeared to be a high plain in the Andes and featured scenery mostly similar to this:
Once we reached the Argentine border control office, it took about an hour and a half to get everyone and their luggage unloaded and processed through immigration and customs.
All together the trip took about 13 hours, a little longer than expected and with a one hour time difference, we arrived at our hotel in Salta, Argentina, at midnight.