Helush Yiraq has long pursued interesting, but also inconspicuous natural phenomena occurring at particular places, and usually highlights their existence via performances. Once in the Prague district of Butovice, she was captured by a ray of light cast through an oval ceiling opening onto the wall and the paving of the local subway station (1988). Just as the station architect, Petr Šafránek, intended, designing a space filled with natural light. The road that roofs the ceiling is south-oriented, and the intervention hence produces both a sundial and a calendar. The station thus generates similar mystery like the British Stonehenge monument and the space behind the St Vitus Cathedral, which viewers witness at sunset during the solstice, phenomena which the artist translated into the title of her diploma work.