Photo taken on Aug. 4, 2017 shows visitors looking at works of Argentinean artist Adrian Villar Rojas at the Athens National Observatory on the Hill of the Nymphs in the centre of Athens, Greece. Celebrated Argentinean artist Adrian Villar Rojas has transformed this summer the outdoor space of the Athens National Observatory opposite to the Athens Acropolis into a "jungle", posing to locals and foreign tourists questions regarding disappearance, extinction, the passage and volatility of time.(Xinhua/Lefteris Partsalis)
