From where I live I can almost see between the walls (of the Helms Deep set). The walls have large walkways on top. At the moment the front wall has 3 of the large ladders against it.
Filming was taking place on the top of the back wall last night. It had 1 ladder against it placed on the inside (between the walls) and the camera and lights were at the back. On the right side of the back wall there was a large flame buring and 2 smaller ones on the front wall. Between the walls towards the back there appeared to be a large fire burning at times and they were producing lots of smoke from the fire and from a large cylinder thing(have no idea what this was….maybe dry ice?).
There was a lot of fighting going on with large swords which appeared to be a silver colour. Some of the cast had arrows in a holder on their back and metal head pieces.(Boy do I wish I had stronger binoculars to get more detail)
There is still a lot of building going on on the bottom wall (there are 4 in total)
Will keep you posted as I see anything exciting.