The Bay of Fundy's tidal bore is one of many aspects of the world's highest tides that fascinates people.
A tidal bore is a wall of water that moves 'backwards' up low-lying rivers during an incoming tide. Tidal bores form when an incoming tide rushes up a river which is flowing down toward the sea. Thus we have the phenomenon of the river changing its flow before your very eyes, flowing in over the outgoing river water.
The height of tidal bores increases with the range of the tide and may very in height from just a ripple to several feet. A tidal bore (bore = crest or wave) is a natural phenomenon which is seen in very few parts of the world. Bay of Fundy tidal bores are seen in many rivers in the upper bay with every tide, twice every 24 hrs, year-round.