Department of geophysics operates the seismic station Prague (PRA). Established at the Charles University (Prof. Václav Láska) in 1924, the station started its regular operation in 1927 and joined the international seismic data exchange. This seismic station played an important role in the development of European seismology (e.g. it was a second station in Europe that started to determine the size of the earthquake using the magnitude value). During the years, due to the administrative changes, the station was successively associated to different institutions (e.g. to the independent State Institute of Geophysics, to the Geophysical Institute of the Czechoslovak Academy of Sciences). Since 1958 the station belongs again to the Charles University and is served by its Department of Geophysics, Faculty of Mathematics and Physics. The instrumental equipment of the station change substantially through the time, e.g. from horizontal astatic Wiechert continuing with electrodynamic Kirnos up to broadband Guralp instrument. The seismic station PRA is part of the Czech seismic network. Its data are supplied to the internationsl seismic center in Newbury (UK), ORFEUS data centre (NL) and are also used for scientific and educational purposes.