In more rural parts of the country you can dive in the unique mountain lakes of Goy-Gel and Maral-Gel which have the cleanest water and depths of up to 90 meters. You can even dive over the sunken villages of Mingechavir reservoir at 15-18 meter depth, or visit Nohur Lake close to the ski-resort of Gabala, as well as many other sites with interesting diving-opportunities.
Close to the Absheron Peninsula, at the east and south of Baku, you'll find a small archipelago of islands most of which are rocky and small with an average depth near from 5- to 12 meters. The waters surrounding them are filled with a small variety of different fish; among the big sea species you may see Caspian seals. Also, in some resort areas you may see an interesting type of black turtle.