[i][b]The next day...[/b][/i]

 "Here it is!"  Wystan exclaimed as he brought the tightly packed ferry up close to the river bank, holding it steady so that they could step off the small craft.  "Right over there...  see it?"  He pointed.  "And right there's where I found them coins."   
 
The opening looked to have collapsed inwards recently and a light, continuous stream of cool air poured from it.  
 
The ferryman whistled as he tied the vessel to a sturdy tree near the bank.  "Here, take these, will ya," he said to whoever happened to be standing nearby, handing them a rope and a lantern.  "I'll grab the pick and shovel."

Jane didn't waste any time, but hurried over to the opening to poke her head instead.  "Oh, it's cold in there!" she exclaimed as she looked left and right.  "And still a bit wet too," she noted, seeing about an inch of river water still covering the floor as far as she could see...  which wasn't very far.  

[img] https://hikemtshasta.files.wordpress.com/2013/04/cascades-plutos-cave-feb2013-047-copy-custom.jpg[/img]