The largest Polish telescope, with a mirror of diameter of 2.5 m (8.2 ft), is currently being built by Astro Systeme Austria (ASA) and will start operations at OCM in 2026.

The land for the observatory was donated to UCN by the Chilean government and it was protected by law for exclusive scientific research, securing the astronomical observations from being affected by possible future mining activities.

Initially it was the summit of Cerro Armazones that was considered as the future observatory site, but after the measurements of the wind speed, the decision was made to settle on a slightly lower side hill, which is not so windswept.

The HPT was installed in 2006, and soon after, on September 28, 2006, the official inauguration of the observatory – initially called the Observatory Cerro Armazones (OCA) – took place in the presence of the German Ambassador in Chile, the president of the Chilean Astronomical Society, the rectors of UCN and RUB, a number of authorities from both universities, and numerous colleagues from ESO, CTIO, and the German Aerospace Center (DLR).

[3] In October 2011, an agreement was signed between the ESO and the Chilean government that includes the donation of 189 km2 of land around Cerro Armazones for the installation of the E-ELT as well as a concession for 50 years relating to the surrounding area.

In 2017 the Leibniz Institute for Astrophysics in Potsdam (AIP) proposed to install a robotic 30 cm Zeiss refractor to support the satellite mission PLATO.

This robotic telescope would stand in place of decommissioned HPT, which by 2017 had accumulated several technical problems, and could not be repaired due to a lack of replacement parts.

Also in 2017 an agreement was signed between the Ruhr University Bochum (RUB) and the Nicolaus Copernicus Astronomical Center of the Polish Academy of Sciences (CAMK) for the "use of observing time at the 0.8-m infrared telescope (IRIS)" by the Araucaria Project, led by Prof. Dr. habil.

Due to its harsh atmospheric conditions, such as dry air and extremely low rainfall, the Atacama Desert is the best place for astronomical observations in the world, providing over 330 starry nights per year.

Solar energy is stored in batteries and used at night to carry out observations, and on cloudy days to maintain essential functions of the observatory, e.g. computers and servers, internet connectivity, water pump, heating, etc.

[13] VYSOS 6 conducted a multi-epoch r- and i-band survey of the southern galactic disk with the prime aim to find new, low-mass pre-main sequence stars and to monitor their light curves.

[17] BEST II and IRIS were used in tandem to monitor in visual and near-infrared domains the Seyfert 1 galaxy WPVS48 and PGC 50427 to study these AGNs' dust distributions through the reverberation mapping.