The urban center of the far end of the Northern Territory (locally dubbed the "Top End"), Darwin is a surprisingly cosmopolitan port town, thanks to its proximity to Asia. Located on the Timor Sea 1,950 mi/3,140 km northwest of Sydney, Darwin is somewhat isolated, but it has a number of good beaches and sights.
Visit the Museum and Art Gallery of the Northern Territory (including the Black Room that re-creates the horror of Cyclone Tracy, which ripped through Darwin on Christmas Eve 1974), Chinese Temple and Aquascene (to watch the fish feeding at night). Other attractions include the botanical gardens, the Mindil Beach Markets (April-October Thursday nights) and the Fannie Bay Gaol (jail).
The Darwin Harbor Ferry goes to the resort area of Mandorah, where you can go to the beach and fish. (Make sure the water is safe before swimming—sharks, saltwater crocodiles and deadly jellyfish have been known to swim offshore.)
Half-day trips will take you to the Magnetic Anthills, the Marrakai Plains (to view buffalo herds) or the Territory Wildlife Park (to see wallabies, crocodiles and more).
Darwin is also the jumping-off point for tours and safaris to Kakadu and Katherine Gorge national parks. Also nearby is Litchfield National Park, a national park without hotel facilities that's accessible only to four-wheel-drive vehicles. Day tours there include a tea break in an abandoned tin mine and visits to waterfalls, hot springs and termite mounds 10 ft/3 m high. You'll also get a chance to see lots of kangaroos, parrots and cranes.