I was very lucky and could to join a daytime visit to the Atacama Large Millimeter/submillimeter Array (ALMA). ALMA is located at 5000 meters altitude on the Chajnantor plateau in the Atacama desert. It consists of 66 high-precision radio telescopes, that have a diameter of 12 and 7 meters, and that can be spread over distances of up to 16 kilometers. ALMA is used to study light from some of the coldest objects in the universe, thus providing insights into our cosmic origins.
In order to reach the ALMA high site you have to undergo some rigorous medical checks at the OSF (Operations Support Facility) located at 2900 meters and endure a bus ride, which completes the ascend to 5000 meters in 45 minutes.