Olsztyn is a city beginning with the letter O. It is located in the Warmian-Masurian Voivodeship in Poland. It is the largest city of Warmia, through which the rivers Łyna, Wadąg, Kortówka and Skanda flow. The city is divided into 23 housing estates and is often visited by tourists due to its several lakes.
Odessa is one of the cities starting with the letter O. It is located on the Black Sea. It is the third largest city in Ukraine in terms of population. It plays a key role in maritime transport, due to having the largest port in the country. It lies on the border of subtropical and continental climates.