This building is at the corner of Hämeenkatu and Uudenmaankatu, and I just thought it looked interesting. Secret decoder ring: When Finnish forms a compound word from a noun and an adjective, usually both parts of the compound participate in noun declension, just as if it were two separate words of a noun phrase. Thus, Uusimaa, the region and historic province where Helsinki is located, is analyzed as uusi+maa and thus in the genitive case becomes Uudenmaan (rather than *Uusimaan). So Uudenmaankatu is “the street of Uusimaa” (or in Swedish, Nylandsgatan). For what it’s worth, Finnish katu is a corruption of Swedish gata, which has an English reflex in the -gate ending seen in English towns of the Danelaw (the region of Norse/Danish occupation a thousand years ago).