Good morning, yes, there are some small caves near the castle, but as we've not been there cannot offer any opinion. I thought they were called Genoa, however a quick on-line search found them to be Genova. I looked at the onlione photos and found that most of them aren't of the Genova Caves at all, but are of Drach, so please don't make that mistake.
I did however find a good YouTube entry YouTube - ‪The Caves of Genova‬‎
The tour groups for these caves are quite small, so it may be worth getting info from their website & contacting them to save a wasted journey.
Hope this helps,
Alan & Katrina
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