If you are staying in the French Quarter, the CBD, or the Warehouse District (collectively known as downtown), the first pilgrimage you must make is to the Avenue Pub, located at 1732 St. Charles Avenue, at the intersection of Polymnia Street. You can get off at Stop #11, St. Charles at Euterpe, or if you miss that, keep a look out on the left hand side of the street, and you’ll see it on the corner, with a balcony on top that is right over the sidewalk. You can get off at the next stop (#12) and backtrack.
Go inside, grab a beer list. Place your order and prepare for awesomeness. Check to see if the Balcony bar is open- while The Avenue Pub is open 24 hours a day, 365 days a year, the Balcony Bar upstairs is only open in the evenings (6 pm – midnight Monday through Thursday; 4 pm – 1 am Friday and Saturday; and 4 pm – midnight Sunday.) The Balcony has few beers on tap, but they tend to be a little more specifically beer geeky than the ones downstairs (though there are plenty of special/great beers down there as well). If you’re around on Friday evening, stop by- most of the time there will be local Beer Advocate folks there, along with people heading over straight from the NOLA Brewing tour (more on that later) and the only consistent cask beer event in town- Firkin Friday!
Since you’re on vacation, get there for Crafty Beer Hour - which is actually two hours - from 4pm to 6pm, when the Pub discounts all their American craft pints (no Belgians, no 10 oz pours) by $2.00. This is every day including weekends.
Honestly, you can kill many hours at the Pub. They have some great food, so you don’t even have to leave for that. And when you’re ready to head back downtown, just stumble to the streetcar stop clutching your $1.25 in exact change, and you’ll be taken there in historic style.