During my honeymoon, my wife and I visited Stingray City and went snorkeling at the nearby barrier reef off Grand Cayman Island. The water was nearly as clear as glass and the whole experience was fantastic.

Ogunquit beach, Maine. You could see the crabs chillin by rocks plus the nearby lobster rolls were incredible.

The Gulf Coast of Florida is just as clear, and pretty much anywhere in the Bahamas and the Virgin Islands.

Maya Bay back in 1986 before anyone had heard of it.