I had been hitchhiking, and given a ride all the way to Mendoza. The good samaritan was Roger, the Canadian. At some point we had to wait an hour or so near Chamical, in the north of Argentina.
There was a roadblock going on, some workers were on strike, demanding better work conditions. We started chatting with two guys who were also standing there waiting, and when it was close to a finish (and the workers about to clear the road) one of them gave us a clear signal that everybody was about to get moving again.