Mariehamn Navigation School is an example of Helsinki-based architect Lars Sonck’s diverse work in Åland. Sonck was active especially in Mariehamn in the 1920s and 1930s. The school building was built in 1937–1938.

The three-storey darker shade red-brick building is situated on a hill in the middle of a low-rise housing area, in the northwest corner of the Mariehamn downtown. Many wooden buildings around the school were already built when Sonck designed the navigation school. It is similar kind of landmark building as the Mariehamn town hall Sonck designed on top of a similar hill in the eastern side of the Mariehamn downtown. Differing from the town hall’s symmetrical windows referring to the classical tradition, the school building is dominated by Functionalist strip windows and circular windows.

The navigation tower on the top of the building has been extended, otherwise, the building has been mainly maintained in its original 1930s style.