Arkhangelsk Oblast eventually spread well beyond the Arkhangelsk Region. The Mezen horses, bred in the Mezen River valley, are rather small but suitable for difficult work and easily survive cold winters. The area of current Arkhangelsk Oblast has always been located on the trading routes connecting central Russia to the White Sea, and, in fact, in the 17th century the White Sea was the main sea export route for Russia. The whole course of the Northern Dvina is navigable, as well as the lower course of some of its tributaries, most notably the Vychegda, the Vaga, and the Pinega. The Mezen is
Onezhsky District Porog; there is regular passenger navigation. There is also limited passenger service on the Onega Bay. Onega is served by the Onega Airport which has weekly passenger flights to Arkhangelsk and to the "selo" of Purnema on the Onega Peninsula. Onezhsky District has a very high concentration of historical, archaeological, and architectural monuments. The district contains thirty-two objects classified as cultural and historical heritage by Russian Federal law, and additionally eighteen objects classified as cultural and historical heritage of local importance. Most of these are wooden churches and chapels. The monuments classified as historical and architectural heritage are the following: