43.4, 28.7
The 1901 Black Sea earthquake (also known in Bulgaria as the Balchik earthquake) was a 7.2 magnitude earthquake, the most powerful earthquake ever recorded in the Black Sea. The earthquake epicenter was located in the east of Cape Kaliakra, 30 kilometres (19 mi) off northeast coast of Bulgaria. The mainshock occurred at a depth of 15 km (9.3 mi) and generated a 4–5-metre (13–16 ft) high tsunami that devastated the coastal areas of Romania and Bulgaria. In Romania, the earthquake was felt not only throughout Northern Dobruja, but also in Oltenia and Muntenia, and even in southern Moldova.
The earthquake was followed by a large number of aftershocks, which continued until 1905; the strongest reached magnitudes of 5.5–6.0 on the Richter scale and were also felt in southern Romania, including Bucharest. After 1905, Pontic seismic activity began to subside, although weak and moderate earthquakes were also reported in subsequent years.
Such events are rare in the Black Sea. In the last 200 years, in the Black Sea region 24 tsunamis occurred, of which two were in the territory of Dobruja. The earliest recorded tsunami in Romania dates from 104, when the city of Callatis, current Mangalia, was badly affected.