According to my Lonely Planet, there is no reason to visit Jammu.
Jammu lies just at the point where the the plains begin to fold upwards into the foothills of the Himalayas. It is still too low to get any of the climactic benefits of the hills. It’s true, there is very little tourist infrastructure here, most use it as a stop-over before heading to the Vaishno Devi temple or going over the pass to Srinagar in the Kashmir Valley. I was staying for other reasons, mainly to visit the Raghunath Temple Library.
Here are some pictures. I will write about them soon I hope!
Main entrance to the Raghunatha Temple. You can’t really make out the huge army presence in this photo, but it’s there:
Main street by the temple:
I was staying in Upper Gujjar Nagar:
The old city of Jammu is a maze of narrow streets and old buildings. 
