We did a little research and learned that the Bolshakovo transmitter near Bolshakovo, Russia is credited as the most powerful mediumwave broadcasting station. This station gave a 2,500,000 Watt world-wide voice to the Voice of Russia on mediumwave (1116 kHz and 1386 kHz). The transmitter fed special cage antennas.
Like many other hams, we became enamoured with radio while exploring shortwave and listening to exotic and distant stations like the Voice of Russia.