ATMs, banks, post office
In Finland all the ATMs where you can withdraw money are marked with a yellow OTTO sign. You should check already in your own country that your own bankcard functions abroad. Just in case also find out at your own bank which is the cooperative bank in Finland.
The post office in Finland is called Posti. You can find post offices in the city centre at Vapaudenkatu 48-50 and in the Seppälä area at Ahjokatu 7. Stamps can be bought at R-kioski, book shops, Sokos department store and also in many smaller grocery stores.