Locks for the boat

We know some you may not have experienced or understand the locks, they are a cement chamber with doors that open and close to fill or empty the water so the boat or towboat and barges can get to the next level of the river or stream.  They may be a short drop/or elevation of 8 feet or as high as 80 + feet.  This is a couple of shots of the locks.

This is Erwin standing on the deck of the boat holding onto a line (this help keep the boat in the correct position)  It is a long way up baby!