I'd love some help identifying this Persian hall runner. If you know what it's called, where specifically it was made, or how much something like this might be worth, I'd really appreciate the info. Here's what I know:

Handmade in Iran
Purchased from Amir Rugs in Richmond, VA in the mid to late 1970s
Measures approximately 32" by 12'
About 225 KPSI, as best as I could count (I'm not sure if I'm counting correctly)
Needs a good cleaning

Thanks for any help you can offer!

Old Persian Hamadan, will look much nicer after a good wash. KPSI is half of what you counted. In this type of rug, unlike Persian Isfahan and Kashan for example, the warps sit completely parallel to each other. The wefts are not pulled on heavily and leave the warps the way they are. That's why you will count every single knot twice. In an Isfahan or Kashan rug, any warp forms a 45 degree angle against the neighboring warp, so you see a loop for a single knot from the back as the other loop is hidden below it. This runner, if undamaged, is worth around $300.