As of writing, there is little known about this region aside from the fact that it is "far away" from Kanto, Johto, Hoenn, Sinnoh and all other regions. It is also still unknown the real world location Unova is based off of, however, judging from the distance it is away from the other regions (which were all based of areas in Japan) it's plausible that it's based on an area other than Japan. There have been rumors that it's based off of New York City in the United States.
Like other regions, pre release pictures indicate that the settlements around Unova are of varying size, most notably this time round being Castelia City. Another feature shared with the other regions is there is at least one cave and forest.
The first landmark shown within Unova was Castelia City (ヒウンシティ - Hiun City), which is located in the center of the 3 Islands that make up Unova. Routes throughout the region are shown to start at 01 rather than 301, reinforcing the fact that Unova is totally independent of the other 4.
There are two differing locations in Pokémon Black and Pokémon White with Black City featuring in Black, and White Forest featuring in White. Black City returns in Black 2, while White Forest returns in White 2.
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