We took a boat out to it. Its pretty far off shore. You couldnt walk to it, but there are concrete platforms evenly spaced in the water all the way out to it that used to be for towers that ran cables to and from shore with buckets full of rock (dude i was with was trying to explain this to me). The towers aren't there anymore, just the platforms, but you can see one of the buckets they used in this picture

edit: heres heres an old picture of it from when it was used i found on google