This well-put-together museum offers a good introduction to Altai culture with a range of ethnographic exhibits, wildlife displays and local art and artefacts, including a room dedicated to the Altai landscape painter Grigory Choros-Gurkin. It also houses a stuffed collection of the local wildlife including a snow leopard and an interesting display on prehistoric life in the region (complete with mannequins living in the most sterile looking cave you've ever seen).
The signage is all in Russian but it's well worth a visit even or those who don't speak Russian.