This is what Fort Morgan's inside stairs used to look like at all 5 corners of the parade wall before Battery Duportail was built within the fort. Only two locations had access to powder magazines.
Oh, man, those knee-creaking stairs. Sensible stair-builders make them with an 8" rise and 12" run, but some sadistic bastard made these with a 12" rise!
At my best, I was hard-pressed to walk up those things without huffing and puffing for a minute or two after. Ain't gonna happen these days, unless hacking out my kidney helps to fix my legs. Plenty to look at at ground level until then.
The little squares in the wall are for ventilation; there's an amazing amount of air moving through the powder magazines (one to either side of that doorway)--and no mechanical assistance.
A really really NICE designer would have added a freaking elevator through that door. Just sayin'.