The Llullaillaco is located on the Chile-Argentina border, next to Paso de Socompa border crossing.
It is the highest archeological site in the world at 6730m. Mummies of 3 Inca children were discovered there in 1999 and exposed at the Salta museum of high altitude archeology (MAAM).
Due to its relative isolation, Llullaillaco is very rarely climbed, being however a rather easy and straight forward ascent from both Chile and Argentina.
No public transportation to Llullaillaco from either Chile or Argentina.
Approach from Argentina is much longer (a 4 days drive from Salta).
In Chile :
Get in touch with the CONAF office in Antofagasta and see if one their Guarda Parque is available to guide you.
Soldiers leave Calama on Mondays to conduct their demining mission next to Llullaillaco. They come back to Calama on Thursdays.
Might be interesting following them. My experience is that they are very helpful and educated.
The easiest way to get there is to rent a car in Antofagasta and take the road 28, direction Paso de Socompa.
You will definitely need a good 4x4 to reach the base camp "las zorritas".
Take 40 liters of petrol extra as backup.
180km from Antofagasta, after passing the mine "la Escondida", turn right 2km after the pumping station (-24.230120° -68.873910°).
From here, several trails are running south. Pick one and head toward a North/South electric line and turn left between posts 306 and 307 (-24.450420° -68.853810°). The trail is well marked here.
2.5 km further you will find a white concrete monolith (-24.451500° -68.829440°). Keep on following the main trail.
16km further, you will find the national park entrance (-24.542010° -68.708370°).
Keep on following the main trail next to Quebrada la Zorritas 16 more km ahead, where the CONAF refuge (-24.621510° -68.587200°) and the military camp stand.
No climbing fee.
In theory, you need a "border zone permit".
The authority in Chile which handles these issues is DIFROL.
You should stop at the "mina la Escondida" checkpoint.
They will get in touch with the carabineros in Socompa, check your Difrol authorization and ask for your return date. Recommended for safety.
If you do not stop there, nobody will ask you for the DIFROL.
Miners will make sure you do not enter the mining site and escort you all the way through the site to the exit.
No authorization required on the Argentina side.
Visit the MAAM in Salta and ask for Christian Vitry. He is a friendly mountaineer/archeologist who was part of the mummies expedition and extremely knowledgeable about Llullaillaco.
Refugio "las Zorritas" S 24.62151º W 68.58720º : 2 beds, no kitchen, no toilets, small stream nearby.
Military facilities are 50m away from the refuge. Soldiers are extremely friendly and helpful. Their presence (including the ambulance) is very reassuring despite the nature of their mission (removing landmines).
Camp 1 - at 4700m.-24.674900° -68.581890° 20 minutes drive from refuge " Las Zorritas" or 3 hours walk.
As you have a car, this camp should not be needed but plenty of space available.
Camp 2 - at 5700m. S 24.70133º W 68.54677º
Perfect flat platform for a 2 person tent. Stream at 10 m. Freezes during the night.
Some odd places at 5500m for small tents. In general difficult due to the slope.
February to September.
Temperatures can reach -20ºC at night.
Clouds usually come in between 1pm and 5pm.
Electric storms may occur during dry season.
Check with CONAF office in Antofagasta - Nelson and Andrea
Waypoints file for GoogleEarth available HERE (WGS84 datum).