Island

When is an island not an island?  When the tide is out far enough...

Glaciers carved Casco Bay's islands and sounds in the last ice age.  Ice covered most of North America more than a mile deep a few thousand years ago. This ice sheet held so much water that sea level was hundreds of feet lower than it is today.  The land is still rebounding, rising after being relieved of the weight of the ice when the great sheets melted.  But the tide of ice melt is rising faster.  One day, not too very far in the future, this sometime island may be a full-time reef.