Bar La Ópera, in the centro histórico on the corner of Cinco de Mayo and Filomeno Mata, has been written up in every guidebook about Mexico City for as long as anyone can remember. So although most of its customers are Mexican, it is also a de rigueur stop on the tourist itinerary for any foreigner who gets thirsty in that neighborhood. It was built at the end of the 19th century, a time when Mexico's strongest foreign influence was not the United States, but France. Hence, as you can perhaps tell from the wall and ceiling adornments in the photo, it is our closest answer to a Parisian restaurant from the Belle Epoque.
I wouldn't go out of my way to eat at La Ópera, but it's a lovely place to get inebriated. Furthermore, the trio romántico pictured above, which plays there every night, is about as good as musicians of this genre get. They know every bolero, ballad and torch song from the Latin American repertoire before 1965. They are in fact the only trio I have found in Mexico City that can play a heartbreaking tune which, decades ago, was a hit for Los Panchos, but today is largely forgotten. It is called Lodo, but also known as Si tu me dices ven. If you go to La Ópera, ask for that number.