This bottles were bought in Salzburg, Austria, directly from the Stiegl brewery, where it is produced.
The trip until the brewery was a surprise schemed by Andreas and Alex, two bavarian friends. I must say that on our way to Salzburg, I could already guess where we were going, but what I didn't know is that Stiegl brewery has the biggest beer museum in Europe. It was an awesome trip.
Both bottles contain the same 5,0% Zwickl beer, in my opinion, one of the best produced by Stiegl. The difference between them is not only the volume (2 liters x 500ml) but also the ocasion in what they were consumed.
The 500ml bottle was drank with a couple of friends after we tasted some cachaça with honey at my place, without much attention gave to the beer. The 2 liters bottle was very celebrated when opened though, we were celebrating a friend's new apartment and I used the ocasion to open my beer bottle number 500th.
It has a special place in my collection, once I aim to achieve 1000 different beer bottles in my life, and this represents half the way to my goal (hopefully I will have enough time to collect a lot more)
Link to the producer:
http://www.stiegl.at/de/stieglat/stiegl-geniessen/stiegl-sortiment/stiegl-paracelsus-zwickl-38/