A Baltic Porter often has the malt flavors reminiscent of an English brown porter and the restrained roast of a schwarzbier, but with a higher OG and alcohol content than either. Very complex, with multi-layered flavors.
May also be described as an Imperial Porter, although heavily roasted or hopped versions should be entered as either Imperial Stouts (13F) or Specialty Beers (23).
Sinebrychoff Porter (Finland), Okocim Porter (Poland), Zywiec Porter (Poland), Baltika #6 Porter (Russia), Carnegie Stark Porter (Sweden), Aldaris Porteris (Latvia), Utenos Porter (Lithuania), Stepan Razin Porter (Russia), Nøgne ø porter (Norway), Neuzeller Kloster-Bräu Neuzeller Porter (Germany), Southampton Imperial Baltic Porter
You can view the complete style details on the BJCP website. The 2008 style guide is obsolete but there is a similar 2015 style that you can view below...