Fallen arch?

I popped down to Hot Walls (inaccurately described today) in Old Portsmouth to visit a ceramicist who has a pottery studio in one of the arches. I had planned to take a view of the open arch towards the sea (extra) but in fact the arches of the heavily fortified wall caught my eye. Presumably they were constructed as gun emplacements guarding the entrance to the Portsmouth harbour but now they have much more peaceful lives The lower one on the far left is a window to a very nice cafe. Thank you Rockarea for your theme of arches today