Ob river

             Ob river (Обь) is a major river in western Siberia, Russia and is the world's seventh longest river (2,962 km (1,841 mi)). It is the westernmost of the three great Siberian rivers that flow into the Arctic Ocean (the other two being the Yenisei River and the Lena River). The Ob forms 16 miles (26 km) southwest of Biysk in Altai Krai at the confluence of the Biya and Katun rivers and empties in the Gulf of Ob which is the world's longest estuary. 
             The main tributaries are: Katun River, Anuy River, Charysh River, Aley River, Parabel River, Vasyugan River, Irtysh River, Northern Sosva River, Biya River, Berd River, Inya River, Tom River, Chulym River, Ket River, Tym River, Vakh River, Pim River, Kazim River. It's crossing the following cities: Biysk, Barnaul, Novosibirsk, Nizhnevartovsk, Surgut.

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Irkutsk

              Irkutsk (Иркутск) is a city and the administrative center of Irkutsk Oblast, Russia, and one of the largest cities in Siberia. It had a population of 587,891. It is situated near Baikal Lake. 
              The main landmarks of Irkutsk are: Irkutsk Bank of Russia (Иркутское управление Банка России), Irkutsk-Passenger Station (Вокзал Иркутск-Пассажирский), Molchanov Siberian Library (Библиотека им. Молчанова-Сибирского), Museum of local lore (краеведческий музей), Irkutsk Clinic of Ophthalmology (Клиника глазных болезней), Decembrist Museum (Музей декабристов), Drama Theatre (Драматический театр), The Roman Catholic Church (Римский католический костёл), Church of the Saviour (Спасская церковь), The former residence of governors-general (Бывшая резиденция генерал-губернаторов), Moscow Gates (Московские ворота), Trinity Church (Троицкая церковь), Lacy house (Кружевной дом), Actor's House (Дом актёра), Kirov Square (Сквер Кирова), Epiphany Cathedral (Богоявленский собор).

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Omsk

             Omsk (Омск) is a city and the administrative center of Omsk Oblast, Russia, located in southwestern Siberia 2,236 kilometers (1,389 mi) from Moscow. With a population of over 1.1 million, it is Russia's second-largest city east of the Ural Mountains after Novosibirsk, and seventh by size nationally. 
             The main landmarks of Omsk are: Tarskaya street (Улица Тарская), Pushkin State Library (Библиотека Пушкина), Mikhail Vrubel Fine Arts Museum (Музей изобразительных искусств им. М. А. Врубеля), Assumption Cathedral (Успенский собор), Omsk plumber monument, Omsk State University (Омский Государственный Университет им. Ф. М. Достоевского).

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Baikal lake Байкал

            Lake Baikal (Russian: о́зеро Байка́л) is the world's oldest lake,at 25 million years and deepest, averaging 744.4 m (2,442 ft). At 1,642 m (5,387 ft), Lake Baikal is the deepest and among the clearest of all lakes in the world. Baikal's age is estimated at 25–30 million years, making it one of the most ancient lakes in geological history.
            Located in the south of the Russian region of Siberia, between Irkutsk Oblast to the northwest and the Buryat Republic to the southeast, it is the most voluminous freshwater lake in the world, containing roughly 20% of the world's unfrozen surface fresh water.

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