Hanoi, March 25 -- The Vietnamese bay, located in the northeast of popular Ha Long Bay in the northern province of Quang Ninh, was ranked third on the list, featuring a more tranquil, less crowded, but just-as-beautiful alternative.

The bay has the same towering limestone islands and karst formations, caves, hidden coves, and floating fishing villages, but with a quieter, more quaint and intimate feel.

The U.S. magazine suggests that visitors opt for luxury boutique cruises and smaller boat tours instead of large-scale cruises.

Highlights include kayaking and swimming in emerald green waters, and eco-tours that explore the awe-inspiring natural wonders of Bai Tu Long National Park. There are also multi-day excursions that allow tourist...