García Márquez based Love in the Time of Cholera on his parents' love story. Read all about it in this short article, called "Serenade: How My Father Won My Mother," published in The New Yorker in 2001.
Cartagena, a city in northern Colombia on the Caribbean coast, serves as the inspiration for the setting of Love in the Time of Cholera. According to this article in the New York Times, a group of historians has been working to identify the real-life places behind the novel's fictional locales.
Gabriel García Márquez used to be BFFs with another famous Latin American author, Peruvian Mario Vargas Llosa. Their friendship ended in 1976, when the two got in a fight over a woman. (Vargas Llosa's wife, to be more specific!) Read all the sordid details, and check out Gabo's black eye, in this New York Times article.