It has often been claimed that the Hyborian Age took place at the end of the last ice age, in which case, today's geography is likely to have significant relevance to that landscape. If, though, as some have suggested, the Age took place before the ice age, then there is much less data for us to work with.

Here's a rough overlay of two REH maps (plus a bit of France thrown in, in the hope of seeing where Tarantia would lie).

Click image for larger version. 

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