Antique Hand Tied Persian Rug

I was wondering what you could tell me about this hand tied Persian Rug. My husband & I got it as a wedding gift 25 years ago from his rich, world traveling, grandmother (who has since passed away) and have no idea of it's value or origin. It is all wool, hand tied approx. 34" x 58" and in very nice condition. We are actually looking to sell it, but want to find out more about it's background and value. I got your name by googling "free antique appriasals" and found your link.
We would be greatly appreciative of any information you could give us.
Sincerely-
M.Dann