Go into the foyer of the impressive Bacardi building (it is now used as offices) in Old Havana and ask for the bar. The lift operator will take you up in his ancient contraption to a perfectly preserved art deco masterpiece.
Old wood and the bat symbol is everywhere. The only drink available was a perfect mojito ($2) when I was there (1999), but who cares? Not one single other tourist, just some staff from the building who had finished for the day.
I was stuck for two hours during an horrendous thunderstorm, it was great. Beats a week slobbing in Varadero any day.
Bacardi building, old Havana