The above image shows Volcán Licancabur and Juriques on the left. The next peak to the right is Volcán Toco. At first appearance it does not seem too imposing a volcano. However, looks can be deceptive. The summit of Toco is 5,604 meters - a very respectable 18,386 feet. On our last day in San Pedro de Atacama, Kevin and I, with a group of others, went on a morning hike to the summit of Toco. I wish I could say that I made it to the summit, but at about 5,400 meters I was hit hard by a case of altitude sickness. Altitude sickness, quite simply, is caused by a lack of oxygen. Symptoms include dizziness, headaches and nausea. I got hit by all three. The only cure for it is to get more oxygen. Since we were not carrying oxygen tanks with us, the only option for me was to head back down to lower elevation. Once I had descended a few hundred meters, the nausea and dizziness passed but the headache persisted throughout the rest of the day, and was only cleared up by a good night's sleep. Despite the sickness and not making it to the summit, I can still claim to have attained the highest elevation of my life, approximately 5,400 meters, or just under 18,000 feet.
Volcán Toco is located almost due east of San Pedro de Atacama at approximately 22°56' S Latitude and 67°47' W Longitude. Toco is a stratovolcano composed of andesite lava flows and pyroclastic deposits, and dacite lava flows. The age of the volcano is Quaternary (1.6 million years to the present). Additionally, deposits of sulfur are found on Toco. Some of these deposits have been large enough to attract mining operations in the past.