Irkutsk is unique because of it's wooden houses right in the city center! There are many beautifully decorated churches and houses with stunning hand-carved ornaments there.
Irkutsk is also the best place to go and see the pearl of Russia - Lake Baikal. We recommend you to take a bus or rent a car and to explore Listvyanka — a village near Baikal Lake. There you can hike hills around the Baikal, take a boat, walk along the ancient railroad around the Baikal, and, once you are hungry, try delicious local lake fish.