April 1923 Kamchatka earthquake and tsunami
On April 14, 1923, at 02:31 local time, an earthquake occurred off the northern coast of the Kamchatka Peninsula in the USSR, present-day Russia. The earthquake had a surface-wave magnitude (Ms) of 6.8–7.3 and an estimated moment magnitude (Mw) of 7.0–8.2.
Source: Wikipedia — April 1923 Kamchatka earthquake and tsunami (CC BY-SA 4.0)