06/19/2026
This is how/ why Lake Champlain formed. Pretty cool!
10,000 years ago, this wasn't land.
After the last Ice Age, a vast arm of the Atlantic Ocean flooded deep into what are now Québec, Ontario, Vermont, and New York. Scientists call it the Champlain Sea.
The weight of the enormous Laurentide Ice Sheet had pushed the land downward. As the ice melted, seawater rushed inland through the St. Lawrence Valley, creating a saltwater sea hundreds of miles from today's coastline.
And yes—beluga whales actually swam here.
Fossils of belugas, walruses, seals, and other marine animals have been discovered far inland, including in Vermont and New York, proving that this region was once part of a marine ecosystem.
Over time, the land slowly rebounded upward, cutting off the connection to the Atlantic and transforming the Champlain Sea into the landscape we know today.
Imagine standing near modern Montréal or Ottawa and looking out over a vast saltwater sea filled with marine life.
Earth's maps have changed more than most people realize.
📍 Champlain Sea
🕒 Approximately 13,000–10,000 years ago
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