Älvsborg

Älvsborg or Elfsborg may refer to:

==Military== ===Fortresses=== Old Älvsborg, a ruined mediaeval castle on the Göta River in Gothenburg, Sweden New Älvsborg, a sea fort on the island of Kyrkogårdsholmen in Gothenburg, Sweden Älvsborg Fortress, a 19th-century fortress at the mouth of the Göta River Fort Nya Elfsborg, a 17th-century colonial fort on the Delaware River in modern New Jersey