Ahh, i have just read somewhere that the College is used as more a nursing home for young Nord nobles now, so im guessing that its true purpose is now forgotten, and we may possibly have to go there to discover secrets of the voice, which will be hard to get close too since the whole area of Whiterun which contains Markarth side
Markarth is to the west in the canyon hold known as the Reach while Whiterun is near the center in the tundra hold known as...Whiterun. Their holds border each other, but the cities are not "close" to each other.
http://www.shareapic.net/Zoom-24969041-Skyrim.html (based on the next two maps)
http://i.imgur.com/L8GxR.jpg
http://www.scharesoft.de/joomla/almanach/images/1/1f/Artwork_-_Art_of_Skyrim_-_Himmelsrand-Karte.jpg (Markarth to the far right, Whiterun near the center).
http://images.uesp.net//3/33/Skyrim_map_Oblivion.jpg (outdated now)