Individual #Baltic_Sea__Baltic  a sea in northern Europe; stronghold of the Russian navy
  instance of:  sea
  part:  Gulf_of_Bothnia  a northern arm of the Baltic Sea; between Sweden and Finland
     part:  Aland_islands__Aaland_islands__Ahvenanmaa  an archipelago of some 6,000 islands in the Gulf of Bothnia under Finnish control
  part:  Gulf_of_Finland  an eastern arm of the Baltic Sea; between Finland and Estonia

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