Statistics for occurrence #1 of “Roanoke Island” in chapter 2 of Admiral David D. Porter, The Naval History of the Civil War.:

...e hundred fine guns, most of which were uninjured. A number of them were quickly mounted at Sewell's Point to keep our ships from approaching Norfolk; others were sent to Hatteras Inlet, Ocracocke, Roanoke Island and other points in the sounds of North Carolina. Fifty-three of them were mounted at Port Royal, others at Fernandina and at the defences of New Orleans. They were met with at Fort Henry, Fort Don...
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Entity Corpus Doc Corpus Doc  
Roanoke Island (North Carolina, United States) 1,553 36 141 0 0 user votes

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