The capital of Siberia is Irkutsk, a city located in the Irkutsk Oblast region of Russia. It is situated on the Angara River, a tributary of the Yenisei River, and is the most populous city in the region. Irkutsk is known for its cultural heritage, with many churches and museums, as well as its proximity to Lake Baikal, the world's deepest lake. The city is also an important industrial center, with a large number of factories and businesses.