Into another world…

Drifting down the river on a warm, breeze less morning with the sun about to rise, they encountered a low mist hanging over the water. It is a common occurrence for that time of year and day; therefore, there was no cause for alarm.
Soon, the mist thickened. In mere moments it turned into a dense fog. So thick, the sun became obscured, and it became uncomfortably dark.
Suddenly the sense of direction and movement ceased. The river became eerily silent.
Then, a slight gust of wind from a previously windless morning pushed the fog away.
The sight before them stunned their senses.
The sun is now setting over the open ocean. No land in sight.