I don't really care for beer, more of a wine/rum/gin guy, but Praguehas beer I would drink.

Any beer in Prague is the best I've ever had!

Hands down, Pliny the Younger from Russian River Brewing Company. Ok, and I'll admit. J.R. told me about this and I've still yet to taste it! 

It's a triple IPA released at their pub the first Friday of every February and is only available for 2 weeks! If you can't make it there, Toronado has a limited amount after it's released as well. Either way, when in SF, go to Toronado for their beer selection. Here's a picture I took last February when I went there to drink Pliny the Younger (was a few days short of Elder!).

If you aren't lucky enough to taste Pliny the Younger, you can find Pliny the Elder by bottle in some bars now across West Coast and Colorado. You might have to specifically ask for it though as most bars don't advertise they have it. For example, I know Manhattan BrewCo. has it right now, but you have to ask! You might already know all of this :)

Another place I love to go for beer is Michigan. Specifically, Bell's Brewery, Inc: Brewery.You can get Oberon, Two Hearted, etc. on the West Coast now, but I love going to the actual brewery.

Prague - the best option

Prague!

I have two answers, a domestic and an international response. The domestic one you're going to want to be sitting down for:

Asheville. Yeah, yeah, everyone loves Portland and San Diego for beer, and deservingly so. But Asheville really gets overlooked and they have some awesome beers, and really cool beer experiences, like Asheville Brewing Company, which makes damn good beer, but then also has a full-on movie theater where you can drink craft beer and order good pizza and watch movies. Pretty legit. Some other great breweries: Green Man, Highland Brewing Company, and French Broad Brewery.

Brussels. Some of the best beer I've had has been in Belgium. And do they ever have a kick. However, if you do one thing in Brussels, as others have mentioned, it's Delirium Cafe. It has the largest selection of beers (more than 2,000) in the world, and is like a alley of beer cafes. You'll leave kicking and screaming. Another great spot Brasserie Cantillon. There are also some good brewery/beer cafe tours in Brussels.

Here is my crack at it:

For drinking beer after beer and having a great time, you got to echo those other people and go with Lagers AKA Prague and Germany. In Prague go to U Fleků. Germany I could drink anywhere and did.

If you want un-hoppy but amazing beer that is a broad range of flavors, high in alcohol and overall diversity, it has got to go to Brussels, specifically Delirium Cafe.

In the US, you cant beat the concentration, diversity and overall awesomeness of beers in Portland but some of my favorite beers are Dogfish Head Brewings & Eats Russian River Brewing Company.

In Portland check out Horse Brass Pub Green Dragon Pub Breakside Brewery 10 Barrel Brewing APEX. 

I love trying local beer and try to look up brewery tours wherever I am visiting. I was at Brewery Ommegang for a Modest Mouse concert and it started pouring, but it was okay! The beer never tasted so good and probably one of the best pizzas I had from a food truck My mouth is salivating just thinking about that day. Cheers!

Prague- especially for its amazing variety of delicious ales and lagers. They're not big on IPAs or porters in the Czech Republic, but the quality of their lagers is head and shoulders above any North American "craft" lagers I've tried so far. Check out "Prague: A Pissheads Pub Guide" for the best places off the beaten track, with much more to offer than just Pilsner, Gambrinus or Staropramen. Also look for "tankove pivo". 

Iceland surprisingly has a really good local beer scene, I really liked their Gull (Gold) beer.

Anything we drank while in Bavaria was also delicious, always just got whatever was on tap or the in-house brew and it was always great.

Belgium and Australia!  Local brew only nothing exported...

Dublin. Duh. Lol

Prague! But even better was taking a beer bath with unlimited beer from two taps while you soaked. I'm not a huge beer drinker, but after that, things changed.

Totally agree with everyone who mentioned Prague! Here's my guide to the best spots for drinking beer in the Czech capital: http://www.guidilo.com/czech-beer-guide

Kalamazoo, Michigan. Arcadia Brewing Company Kalamazoo, Bell's Brewery, Inc: Brewery. They are building a Brewing College there for those that want to learn the Art.

Koelsch in Cologne (Koeln), Germany. It's really light and deliciously crisp. Tastes like more! Yum.

Oh, and you must try Trappist beer in Belgium. 

Prague and many of the small local breweries all around the country, Belgium, New Zealand :-)

Definitely Prague  Not only is the beer at every brewery great, it is very reasonably priced!!

Prague and Budapest

Portland in Oregon, but also Prague, in Czec Republic :)

Drinking beer is like eating , that depend on each people. Personally, drinking and eating become more exciting with the "environment" at that moment . There's still a lot places I didn't visit yet so till today Belgium is the best place to drink the best beer.

Alaskan Brewing Company brewed in Juneau is awesome.

Vilnius, Klaipeda, Trakai... LITHUANIA

Definitely Gambrinus beer in Prague

Asheville - aka Beer City, USA. There's a beer or brewery for everyone. My favorite is Wicked Weed Brewing for their eclectic brews and fun atmosphere. The beers rotate with seasonal flavors and my current favorite is the Imperial Coolcumber. It's aged in gin barrels and infused with cucumber and basil. And Asheville itself is a wonderful little place to visit- chock-full of character, hiking, and local crafts. 

I can't remember the single best beer but the best beer destination I have ever been to is Asheville. There are so many different breweries in such a small area, it is wonderful to try them all.  By far my favorite of the 20 we tried were Wicked Weed Brewing or Burial Beer Co.!

Colorado, final answer.  :-)

If you love beer, you must come to Colorado.

San Miguel- Pale Pilsen and Mexico- Dos XX ...

Australia!

Wisconsin. . . Duh. Seriously tho as a purest at heart of brews not into IPA craze. Wisconsin is known and celebrated for their tasty beer and welcoming atmosphere and people. I love summers there. A super summer venue is Summerfest in Milwaukee. I try to visit yearly.

I love beer with some carracter. Sorry but pale ale does nothing to me.  I just love my voyage to Great Britan where every pub has it's own favorite. 

We just step up to the counter, ask for what was local and had wonderfull discoveries. Never took the more commercial beers, stuck to what was on tap of there local favorite.  No disapointments with this approche so far !

NY New York city bar St. Gambrinus Beer Shoppe-White unfiltred

Short's Brewing Company, Bellaire, Antrim County, MI.

Asheville, NC   Several really good micro breweries.

Swamp Head Brewery, Gainesville, FL

Bruges, Belgium!

I never cared for beer until I tried Japanese beer!

Belgium. Without a doubt. They have more types of beer than you can care to think about and they also have excellent tours of the breweries - something I took advantage of once at the Duvel Moortgat Breweryand wrote about too: http://www.unexpectedtraveller.com/Blog/things-to-do-in-and-around-brussels-tour-the-duvel-brewery/

Sergio's World Beers in Louisville, KY. Sketchy neighborhood, but they have more beers to choose from than I've ever seen. 

London! Best place for a good pub crawl!

OK, this is a little off the point of your question. I assumed a lot of people would mention Czech Republic, Belgium, UK and the USA. But there are countries you don't think of right away that have thriving, under-the-radar beer cultures, and one is Italy. If you happen to be in a place like Venice,  look for a birraria -- basically a craft beer bar -- like Birraria la Corte. The food's not bad either. Try a Birra Amarcord S.p.A. (that's the brewery -- Birra Amarcord is the brand).

I'm not a great beer lover but Dublin has great, locally brewed craft beers. A couple of years ago I tasted a few beers in Berlin and was almost converted!

Tough one. Probably Portland. I've had the best results hitting bars with wide selections of regional craft beers.

There's one cool thing happening in Prescott, though: It's one of the few places in the country with a meadery and a tasting room (Superstition Meadery). 

I'm tempted to mention Denver, but it's much more spread out and heard to hit a bunch of different places.

London, England at a restaurant that serves Belgian food and beer. 

As well Czech Republic. Moreover, one of the few countries in the world where pint of beer is cheaper than pint of coke. :-)

I have to admit, the beer I drank in Prague was pretty good. But my favorite spot to enjoy a cold, freshly tapped beer is Bavaria. They usually serve the beer in very large jars, called "Mass". But I also like the beer brewed in northern Germany. It is more bitter than in the south, but also delicious. 

Province of Florence! My best beer ever here!

London!