This is a large rifle at Fort Fisher in North Carolina. Described as a 6 3/8 inch rifle (Old 32) it forms part of Sheperd's Battery and faces the landward approach to the fort. Presumably the hill on the right of the gun would protect the position from fire from ships off shore. This view would be directly towards the ocean.
I started a sand fort project designed to depict a large sand mound and gun positions. The basis is green florist's foam, and as this pre-dates my hot-wire cutter, it was glued down with hot glue in various layers and carved to shape with a knife and "Surform" tool.
Rodman 10 inch guns look out over the St Mary's River at Florida's Fort Clinch. There is a fascinating history at this very well preserved fort, but its ownership was never contested by fire.
Pulaski however took the full brunt of the Union rifled artillery:
Fort Pulaski, near Savannah in Georgia. Plenty of model building potential here!