I know its most likely answered, the GSM emergency number, 112.
The number is carrier independent, and towers are programmed to take the call, no questions asked. In times where a tower is operating at maximum capacity due to number of phones connected (say a sporting event nearby), a tower will actually drop active calls to take an emergency call.
I dont know about other countries, but in Australia, 112 *OR* 000 (Australia’s emergency number) will work. It would not surprise me if they programmed 911 for the American Tourists, and 999 for the British tourists 🙂
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