File:Cultural regional areas of India.png

Summary
Map of Indian subcontinent illustrating stability and historical permanency of the regional cultural frontiers and areas.

Map reference: at University of Pennsylvania.

Comments
I must say, I'm not quite comfortable with this map. I believe that this map should not be used in a Wikipedia article. According to Wikipedia's guidelines, all information in the articles should be verifiable. The problem with this map is that the terminology applied is not defined. What exactly is a 'regional cultural area'? What is a 'culture'? Is it a linguistic subdivision, is it a historical state, or is it an area with a specific mode of agricultural production or what? As long as we don't know what it is, the content is not verifiable. The link to the University of Pennsylvania does not help, it only demonstrates that the problem is duplicated in their materials.