Ymer is the fifth and last icebreaker in the Atle-class. She was launched in late 1976, and on 25 October 1977 she was delivered to the Swedish Navy and departed the Wärtsilä Helsinki Shipyard bound for Stockholm, where she arrived on 3 November.

• PDF from Swedish Maritime Administration Archived 2014-01-06 at the Wayback Machine
• Newspaper article about Ymer (in Swedish)^{[dead link‍]}