Former distribution of hypothetical and attested Indo-Iranian dialects on the Natural Earth 1 shaded relief map with key on the left. 
Note: Partial shading denotes another unrelated language being spoken in the area either bilingually or in separated communities, or rather simply the possibility of the presence of an Indo-Iranian language in that area. Para-Indo-Iranian may or may not have existed at all, hence the question mark at the end of the label, although genetic and material evidence highly suggest that it did exist, even if spoken solely by a bilingual population.
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<a href="//commons.wikimedia.org/wiki/User:AQUILIBRION" title="User:AQUILIBRION">AQUILIBRION</a></div>
CC BY-SA 4.0
<p><span class="int-own-work" lang="en">Own work</span>, using
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<ul><li>Coastline, lakes and rivers from <a rel="nofollow" class="external text" href="http://www.naturalearthdata.com/downloads/50m-physical-vectors/">Natural Earth 1:50m Physical Vectors</a></li></ul>