Castle Bravo was the first in a series of high-yield thermonuclear weapon design tests conducted Action by the United States at Bikini Atoll , Marshall Islands , as part of `` Operation Castle '' .

Castle Bravo 's yield was 15 megatons of TNT , 2.5 times the predicted 6.0 megatons , due to unforeseen additional reactions involving Cause_to_be_included Li , which led to Causation the unexpected radioactive contamination of areas to the east of Bikini Atoll .

The Bravo Crater is located at .

The remains of the Castle Bravo causeway are at .

The following day , rebel leaders Juan López de Padilla , Juan Bravo , and Francisco Maldonado were beheaded Killing .