Theoretically, a barrier island is there to protect the mainland from harsh weather.
Barrier islands are a permanently exposed “mountains” from the bottom of the ocean made up of sand and rock and pebble. A lot of barrier islands are developed – as you drive to a barrier island you inevitably cross a bridge that is over an estuary (bay).
Two of my favorite barrier islands are Stone Harbor/Avalon in N.J. and Hutchinson Island in FL.
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