Bannerman's island is near where I used to live in New York. It's just south of Newburgh on the East side of the Hudson River.
There is a gothic "Castle" on the island, and it looks like a group is now working to preserve it:
Bannerman's Castle
When I lived in NY, I had a boat and taught Scuba Diving. Bannerman's Island (at the time the property was posted and off limits) always had the allure of mystery. It's interesting to see the activities going on there now... Gardens... Castle restoration... Perhaps hidden Lugers?
I also worked for IBM in Poughkeepsie. This is the plant that assembled M1 Carbines for the US in WW-II. There was a persistent rumor that after the war, IBM dumped case after case of cosmoline packed M1 parts into the Hudson. We never found any trace, but it's deep, dark and muddy on the bottom of this estuary (which flows in and out with the tides)...
Marc
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Igitur si vis pacem, para bellum -
- Therefore if you want peace, prepare for war.