Fast... when the tree pierce the hull initially it sank to the bottom of the river which wasn't all that deep in a few minutes(5 to 8 feet of water) ..... the next morning the only thing visible was the top of the Smoke Stacks. The river water needed a path around the boat and the easiest way was under it so the river buried the boat.
Great experience, 10 yr old loved the tour and seeing all artifacts. Even had visit from one of the original members of the team dig the day of visit.
Sank pretty quick. From the tour guide as the story goes
Overnight
It was very fast. I believe it was something like 11 minutes.
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