I was in Fort Benton, MT, still early in the trip.  I was on my early morning walk/run on a path close to the River.  In the early morning faint light, I came upon a deer standing in shallow water very near the bank.  I slowed, then stopped, not wishing to disturb.  After what appeared to be some consideration, it apparently decided it didn’t want to share the space with me.  It turned toward the river, and began bounding away.  “Oh, wow”, I thought, “I’m not sure I’ve ever seen a deer swim!”
I didn’t then either.  The deer continued bounding all the way across the River and up onto the bank on the other side, never even getting close to knee-deep.  Despite appearances and width at that point, the River was that shallow!  I stood for a few moments, transfixed, before I was able to continue. It was just so unexpected, and so amazing.