Cape Neddick, Maine, with its iconic "Nubble" lighthouse, is an easy escape from Boston. Along the way, soak up the sun in Cape Ann, Massachusetts (stay at the Blue Shutters Beachside Inn, Gloucester, from $125), grab a great lobster roll in Portsmouth, New Hampshire, and know that you're spending a bit less than all those folks crowding New England's more famous cape.
The Great Blue Hole is the most popular dive destination in Belize. This massive hole under the water is near the Lighthouse Reef and creates a perfect circle of deep blue water. The water is 407 feet deep. It's breathtaking.