N. Kósa Judit - Szablyár Péter: Underground Buda - Our Budapest (Budapest, 2002)
"Eppur si muove" - the Seismological Observatory on Sas Hill
At the same time, faults in the wall lining made of Sóskút limestone were also repaired, and the water leakage that led to freezing in winter was also reduced. Several plans have been made in recent years for the addition of another track. To accommodate this, an arching line section with a radius of 600 metres was meant to be built east of the existing tunnel. However, real estate price inflation together with the modified functions of the Southern Station (for example, termination of freight handling and the phasing out of industrial lines) prompted the preparation of large-scale plans for new construction work over the utility areas of the station, and it was also suggested that the M2 metro line should be continued on the surface from the Southern Station all the way to the Gazdagrét area. Whatever the future may hold, the old tunnel is sure to continue playing an essential part in the life of the railway station. Motorists driving along Hegyalja út from Elizabeth Bridge towards their destinations at Lake Balaton or in Vienna have little idea when crossing the junction at the Mészáros utca traffic lights that deep below them an Intercity train may be pulling into the Southern Station. Nor are children busy drawing steam engines in the Avar utca nursery school much more likely to stop and consider the fact that iron monsters are tearing away some ten metres beneath their feet... "Eppur si muove" the Seismological Observatory on Sas Hill Rising above a sea of buildings, a 259-metre-high biological reservation can be found on the top of Sas Hill. It was declared a protected area on account of its flora "left behind” by the ice age and its varied fauna, which is particularly rich in arthropoda. Led by an expert guide along the exhibition paths among the barren cliffs, the visitor may not suspect that deep inside the hill are sensitive instruments measuring the tiniest tremors of the earth's crust, since on the border of the nature reserve, in Meredek utca, there is the Seismological Observatory of the Hungarian Academy of Sciences. It is mainly when a major earthquake occurs abroad — or, luckily, far less frequently, at home — that the public can see on television the specialists of the observatory explain the data registered about the disaster by the instruments located in the underground research unit. Observing earthquakes has been a major preoccupation of mankind ever 49
