What is the setting of The Valley of Horses: A Novel by Jean M. Auel?

The novel is set during the Ice Age, in a time when Cro-Magna people coexist with Neanderthals. Through the course of their Journey, Jondalar and Thonolan follow the course of the Great Mother River, a description of which suggests it might be the Danube River. Jondalar and Thonolan come to live with the Sharamudoi people during their journey, who live in caves cut into a sheer cliff along the course of the river.