If you needed another reason to visit Halong Bay—often hailed as the world’s Eighth Wonder—the limestone outcropping that is Cat Ba Island in Vietnam is it. The best way to explore the natural wonders of this little-known island—home to the remarkable Trung Trang Cave, cascading waterfalls, cliffs, and the awe-inspiring National Park—is via motorbike. A four-hour ferry ride from Halong Wharf will get you there, but be warned that accommodations are sparse and basic. If you’re not one to get fussy about lodgings, you’ll have no problem staying awhile on this untouched, unspoiled masterpiece by Mother Nature.