1. Baltic Sea, Poland, approaches to Gdynia and Gdańsk Yale Public content 1994. 2011-12-05T17:19:34Z. 2015-10-21T15:07:14Z. United States. Defense Mapping Agency. Hydrographic/Topographic Center. The Center. English. Public. Gdańsk, Gulf of (Poland and Russia), Poland, Gdynia, and Gdańsk.