The first margarita was poured and served in Ciudad Juarez, Mexico. Yes, you read that correctly. It didn't happen in any beach where they are usually consumed at. The story goes like this...
During the Prohibition Era, when countless Americans crossed the border to have a legal drink, a women walked into, the now world-famous, Kentucky Bar. She didn't know what she wanted so the bartender Lorenzo decided to mix tequila, limes, and salt. To this he added ice, shook and served it to her.
When she asked what it was called, he asked her, "What is your name?" to which she answered, "Margarita." At that moment, the margarita was born.
The Margarita’s is reported to have been created first anywhere between 1936 and 1948. There is even a plaque with news clippings and a story on the menu at Kentucky Bar. It is located right on Avenida La Juarez which is the same street you walk onto when you cross the border bridge to Ciudad Juarez.