Relief depicting a mermaid on a horse challenging a raging storm. She is holding a horn as a symbol of the beginning struggle.
The picture is difficult to see.
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Annotation
The building, by architects Ola and Ethel Hansson in 1955, originally housed the head offices of Suomen Höyrylaiva Oy, and the work symbolizes the struggle between the merchant marine and the sea.
Sculptor
Carl Gustaf Mattias 'Matti' Haupt (St. Petersburg 1912 - Helsinki 1999),
Finnish sculptor
(Wikipedia).