The lower half of the river is a tidal estuary occupying the "Hudson Fjord", which formed during the most recent period of North American glaciation estimated at 26,000 to 13,300 years ago.
The lower half of the river is a tidal estuary occupying the "Hudson Fjord", which formed during the most recent period of North American glaciation. This North American glaciation is estimated at 26,000 to 13,300 years ago.