Don't see it. I mean they look alike, but then again so do many of the towns from medieval history that had the same function... Whiterun is also far heavier fortified then Edoras, is build more on the same level with just Dragonsreach standing on top of it...
It's not just the town, Whireun hold is identical to Rohan, the landscape, the colouring, the grass, the hills, the mountains, the people, the buildings etc, the capital is in the same location and the tow is very similar, even the inside of Dragonsreach is exactly the same as the inside of King Theoden's hall, watch the movie.