World's Most Powerful Transmitter?

Recently we were operating and enjoying making contacts around the world on our HF station running 100 Watts of power. Pondering the wonder of doing so much with so little got us thinking about the opposite of QRP - extreme station power. What is or was the highest power radio station in the world?

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.