Dotted with lighthouses along its shoreline, Portland, Maine is a coastal gem in the northeastern United States and a veritable paradise for lovers of fresh seafood, craft breweries, and small-town charm. At the center of downtown Portland, the Old Port neighborhood boasts a number of unique and historical buildings, trendy restaurants and bars, and picturesque views of the Portland Harbor.

Halong Bay, located in northeastern Vietnam, is a stunning UNESCO World Heritage site known for its emerald waters and towering limestone islands. This natural wonder offers a variety of activities for visitors, including cruising, kayaking, snorkeling, and exploring extraordinary caves like the Sung Sot.

Yokohama, Japan's vibrant port city, offers a delightful blend of historical charm and modern excitement. Located just a short train ride from Tokyo, Yokohama is renowned for its picturesque waterfront and cultural attractions.

Patmos, a gem in the Aegean Sea, is steeped in history and spirituality, offering a serene escape for travelers seeking both tranquility and rich cultural experiences. Known as the "Island of the Apocalypse," Patmos is famously where Saint John the Theologian wrote the Book of Revelation. Visitors can explore the sacred Cave of the Apocalypse, a UNESCO World Heritage Site, where the saint is said to have received his visions.

The Yangtze River, a magnificent artery of China, stretches over 6,300 kilometers (3,917 miles) from the Tibetan Plateau to the East China Sea. As the longest river in Asia and the third longest in the world, it weaves through breathtaking landscapes and vibrant cities, making it a prime destination for travelers seeking both adventure and cultural immersion.