If you ever wondered why Octoberfest is held in September, it's because of the better weather. Can you blame them? Celebrate the German beer holiday in Boston at the city's oldest Octoberfest celebration. This Friday the OFest Reception includes four beers, a beer stein, German music, games, and the ceremonial tapping of the keg with Jim Koch. The Saturday OctoberFest is a 10-hour long traditional German Beer Hall event, with two live bands all day, table games, and more than 10 different styles of Sam Adams beer.