A picture is worth a thousand words:
...but just to add a few more, I was boating up the river when suddenly my boat disappeared and I was left standing in shallow water next to this mine hole. Wjt? Vgh? Blefrg?
I don't know what the deal with those chairs is, either. Anyway, I can't get down the mine hole to find out if my boat is at the bottom, because it says there's no room at the exit when I try (perhaps the ruins of many hapless boats that have come before.)