There are catacombs below the Old Dutch Church. They used to have tours of them but I'm not sute if they still do. You can call the church and ask questions. The secretary's name is Pat Hall.
I would start with calling the church first. And take it from there. Sounds exciting/ interesting. Now i want to go. Im going to check out the old mines /caves here by the water front. My son and his friends all went and they told me about the under ground waterfalls. My son is 23. So not little. Just throwing that in there. He brought me back a big rock full of Crystal pieces. Gold dust on top. So of course i want to go and see the beauty there and take photos. Maybe bring back more crystals. :) You really do learn something new everyday. I didn't know about the old dutch church having that. Im going to look it up now while i have coffee. I hope you get to go. Sounds amazing.
I can not... I suggest asking the Google and contacting chamber of commerce or one of the many welcome centers that have tourism info... there is also some I Love NY app that may have info. There's Howe Caverns not too far away
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