La Bodeguita del Medio is Havana's most famous bar for mojitos — a small, packed, loud establishment half a block from the Cathedral of Havana, its walls entirely covered in signatures, declarations, and graffiti left by decades of visitors. It opened in 1942 as a grocery store and became a bar and restaurant over time, attracting writers, musicians, and politicians in the years before the revolution.
The mojitos are genuinely good — mint, lime, rum, sugar, soda, in the proportions that Havana settled on over the 20th century. The restaurant in the back serves decent Creole food: black beans, rice, plantains, roast pork. Go early (before noon) or late in the afternoon to avoid the worst of the tour group crowds. Expensive by Cuban standards, but the original Old Havana bar experience is worth the premium once.