Strongest earthquake in modern Czech history: 40 years ago in 1985
Earthquakes are typically associated with Japan or California, not central Europe. However, in December 1985, the western part of what was then Czechoslovakia was struck by the strongest earthquake of modern times, shaking buildings near the border with Germany and reminding us that seismic activity knows no boundaries.
Although Czechia is not located at the boundary of major tectonic plates, its Earth's crust is not completely stable. Tension can build up and occasionally release in the form of tremors. The most active area is the Cheb Basin in western Bohemia, right at the German border. It is here that so-called earthquake swarms often occur—a series of smaller tremors that can last for weeks.
The Earthquake of 1985
On December 21, 1985, just before Christmas, seismic activity in western Bohemia reached its peak. At 11:16 AM, an earthquake struck the area with an epicenter near the village of Nový Kostel, at a depth of 8 km. It reached a magnitude of 4.6 on the Richter scale, making it the strongest earthquake recorded in the modern history of Czech lands.
Within a 20-kilometer radius of the epicenter, walls of buildings cracked, plaster and roof tiles fell, and several chimneys collapsed. In some wells, the water disappeared, while mineral springs in Františkovy Lázně changed their flow rate. Although the tremor was relatively weak on a global scale, local residents were shocked—some fled to relatives, while others even slept in tents despite the December cold.
Seismic activity continued in the following days, but no further tremors reached the strength of the main one. Experts estimate that the maximum possible magnitude for the Czech region is about 5.5 on the Richter scale, and geological findings suggest that earthquakes of magnitude 6.5 may have occurred here in the last 20,000 years.
