Poel or Poel Island, is an island in the Baltic Sea. It forms the natural northern and eastern boundaries of the Bay of Wismar on the German coast. The northern coast of the island is also on the south side of the large gulf known as the Bay of Mecklenburg, which Wismar Bay enters into. Insel Poel thus forms on its northern side the unofficial latitude of the northern boundary of the Wismar Bay.

Wismar, officially the Hanseatic City of Wismar is, with around 43,000 inhabitants, the sixth-largest city of the northeastern German state of Mecklenburg-Vorpommern, and the fourth-largest city of Mecklenburg after Rostock, Schwerin and Neubrandenburg. The city was the third-largest port city in former East Germany after Rostock and Stralsund.