The world's largest coral reef system, the Great Barrier Reef stretches almost 1500 miles into the Pacific from the tip of Queensland. Designated a Marine Park by the Australian government and a World Heritage Area by UNESCO, the reef is home to an extraordinary abundance of species and habitats. Snorkelling, diving and fishing are popular along the reef, nowhere more so than on the Whitsunday Islands, where the silica sands and aqua waters of the Coral Sea create the perfect beach escape.

Seminyak boasts some of the most glorious beaches in Bali. Be sure to catch the legendary sunsets and enjoy the tranquil beauty, and marvel at Balinese ceremonies on the beach, complete with gamelan players and offerings to the gods. Of course, don’t let the smooth sands and intricate cultural experiences distract you from spas and shopping! Sophisticated spas and high-end boutiques will entice you away from the waterfront—for a short time, anyway.

Bali is a living postcard, an Indonesian paradise that feels like a fantasy. Soak up the sun on a stretch of fine white sand, or commune with the tropical creatures as you dive along coral ridges or the colorful wreck of a WWII war ship. On shore, the lush jungle shelters stone temples and mischievous monkeys. The “artistic capital” of Ubud is the perfect place to see a cultural dance performance, take a batik or silver-smithing workshop, or invigorate your mind and body in a yoga class.

Singapore is known as a bustling metropolis that also happens to be one of the cleanest and safest cities of its size in the world. (Just make sure you heed the local laws—something like spitting in the street might merely be considered rude in your hometown, but here, it carries a severe penalty.) You'll find historic sites like the Thian Hock Keng temple, superlative shopping (including gargantuan malls) and numerous beaches.

Nha Trang is best known for its beautiful sandy beaches. But visitors will also find amusement parks, mud baths, golf, and the historic Po Ngar temple complex, as well as a variety of hotels and restaurants. Adventurous foodies can sample bun cha ca, a soup made from sailfish and jellyfish.

Da Nang is laid-back and friendly, maybe because everyone you meet has just finished an amazing meal. Culinary tours are a hugely popular way to experience literal local flavor. After you’ve stuffed yourself with bold noodle soups and savory street foods, walk it off by exploring the limestone caves and Buddhist grottos of the Marble Mountains.

Phuket offers a rainbow spectrum of spectacular holiday sights from blue lagoons and pink sunsets to orange-robed monks. Three wheeled-Tuk Tuks, taxis, buses and long tailed boats transport visitors between these marvels. Phuket's south coast offers its most popular beaches. The north is more tranquil. Koh Phi Phi, Phang Nga Bay and Patong Beach are popular spots. Diving, snorkeling, wind surfing and sailing are just a few active options. Inland, forested hills, mountains and cliffs wait to be explored.

Just 80 km north of Phuket, Khao Lak was essentially erased by the 2004 tsunami. But the town, and the tourist industry it relies on, has rebounded. It remains quieter than other coastal destinations, offering secluded beaches, tranquil nights and family-oriented activities. You want full moon parties and besotted nights? You’re out of luck. But if you’re looking for unparalleled scuba diving in the Similan Islands, you’ve hit the jackpot.