Sunken Forests of New Hampshire

Trees of these forests sank below sea level after the ending of the Wisconsin glaciation (approximately 11,000 years ago) and subsequent rise in temperature; isostatic rebound has not kept pace with the rise in sea level, and former coastal forests were overtaken by the Atlantic Ocean.

[2][1] Fishermen have hauled up mastodon and mammoth teeth dozens of miles offshore, suggesting the forest extended quite far.

[1] Newspaper reports of other sightings include a 1931 investigation by a professor from Dartmouth College who identified the stumps as "swamp cedar".

[2] The transatlantic telegraph cable laid in 1874—which ran from Rye to Tor Bay, Nova Scotia, and then to Ireland—went through this sunken forest.

[2][4] A newspaper report in August 1933 noted that stumps of the forest and "a section of the old Atlantic cable" could be seen during an extremely low tide.