On 17 Sep 2021 Latvia Post issued the latest in it’s long-running series of lighthouse stamps. Irbe Lighthouse is the only offshore lighthouse in Latvian waters and was completed by the Soviet Union in 1985. The lighthouse is located on a shoal in the Irbe Strait between the Baltic Sea and the Gulf of Riga.

Thanks to Klaus Hülse for information about this stamp.
See more lighthouse stamps from Latvia here