There isn't any. All that we know is that it's an area around an inland sea and some of the Easterling tribes come from there. Apart from that, there isn't really any info. It's plausable that the land is largely grassland and woodland as several of the major Easterling incursions were by forces with a large cavalry and chariot/wain element, although it's also plausable that those tribes were from further East.