what's the best destination from New York City for a 3 day romantic trip?

prefer a beach - can fly or drive - would like low key nightlife - thanks By greenex23Montauk, NY or Niagra Falls.

Montauk is surounded by beach.
www.ilesdelamadeleine.com
Try out the iles De Madeleine

The beaches will be empty, the sea warmer, and some great folk music in the evenings.
St John US VI