When you first look at Iruya on the map there's nothing to encourage you to visit it during your trip to Argentina. That would be a serious mistake!
Iruya is one of those places that is described as being "at the ends of the earth". You don't really need to go as far down as Ushuaia. The end of the world is 80 km from Humahuaca. I got there after 3 hours of winding roads, and crossing over a mountain pass at 4,000 metres. It's not the most original thing to say about Argentina but, the scenery was magnificent! During the journey my bus passed herds of donkeys and I saw vicunas skipping across the mountains. Iruya is huddled into a cliff. The church is really cute and the cobbled streets are very steep. On the corner of a street I met a woman selling empanadas. They were absolutely delicious.
I hope Iruya manages to retain its atmosphere of a village lost at the end of the world for a long time to come.