Rifled muzzle-loading gun at The Citadel, Halifax, Nova Scotia, Canada. Appears to be an <a href="https://en.wikipedia.org/wiki/RML_7_inch_gun#RML_7_inch_7_ton_gun" class="extiw" title="en:RML 7 inch gun">RML 7-inch 7 ton Mk I gun</a>.
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