Kakadu and the Top End, where the wet season redraws the map

The Top End is what Australians call the tropical northern part of the Northern Territory, around Darwin. It is a world away from the dry red centre and the temperate south: a land of monsoon forest, savannah woodland, sandstone escarpments, rivers, wetlands and crocodiles. Its climate is ruled by the monsoon. From around November to April comes the wet season, with heavy rains, thunderstorms, high humidity and the occasional cyclone. From around May to October comes the dry, with clear skies, warm days and cool nights.

The Bininj and Mungguy people, the traditional owners of the Kakadu area, recognise not two seasons but six. Each is defined by the weather and by changes in plants, animals and the food available, from the first build-up of storms to the cooler months when the grasses dry. The calendar reflects tens of thousands of years of close observation of the country, and it is a better guide to the landscape than any European division of the year.

Kakadu

Kakadu National Park, east of Darwin, is one of the largest national parks in Australia, almost the size of Wales. It is a World Heritage Site for both its natural and its cultural importance, and it is jointly managed by its traditional owners and the national parks service. It runs from the coast across vast floodplains and wetlands to the sandstone escarpment of Arnhem Land, cut by gorges and waterfalls.

The rock art of Kakadu is among the most important in the world. At Ubirr and Burrungui, also known as Nourlangie, the rock shelters are covered with paintings, some of them thought to be many thousands of years old, others painted within living memory. They show animals, fish and people, ancestral beings and, in some, the first Europeans to arrive, with their ships and guns. Many are in the X-ray style, showing the bones and organs of the animals depicted. Rangers explain the stories behind them, and the view from the top of the rock at Ubirr, over the floodplain at sunset, is one of the finest in Australia.

Wet and dry

The difference between the seasons is dramatic. In the wet, the rivers burst their banks and the floodplains become vast shallow lakes, green with new growth. The great waterfalls of the escarpment, such as Jim Jim and Twin Falls, are at their most powerful, though often only visible from the air, because the roads to them are flooded and closed. Some parts of the park are cut off entirely.

In the dry, the water retreats to the rivers and billabongs, and the wildlife concentrates around them. That is the best time to see it. Boat trips on the Yellow Water billabong pass saltwater crocodiles basking on the banks, and great numbers of birds: jabirus, egrets, kingfishers, sea eagles and magpie geese. Swimming is dangerous anywhere crocodiles may be, and the warning signs should always be heeded.

Saltwater crocodiles deserve their own word of warning. They are the largest living reptiles, males sometimes reaching five or six metres, and they live in rivers, billabongs, estuaries and the sea throughout the Top End. They are dangerous, and they can be present in water that looks harmless. The rule is simple: swim only where it is clearly signed as safe, keep well back from the water's edge, and take the warning signs seriously.

Katherine and Darwin

South of Kakadu, at Katherine, the river has cut a series of deep sandstone gorges in Nitmiluk National Park, explored by boat or canoe. Darwin itself is a relaxed, multicultural tropical city with a dramatic history. It was bombed by Japanese aircraft in 1942 and almost destroyed by Cyclone Tracy on Christmas Day 1974. In the dry season, its beachside markets at sunset are a local institution.

Travelsphere's Highlights of Australia, twenty-one nights, includes Darwin, Kakadu National Park and Katherine, along with Melbourne, Sydney, Uluru, Alice Springs, Cairns and Brisbane.

Travelsphere's Highlights of Australia with New Zealand Add-on, thirty-nine nights, includes the same Top End stops and adds New Zealand, with Auckland, Paihia and Rotorua.

For most visitors, the dry season, from May to October, is the time to go, when all the roads are open and the wildlife is easiest to see. But anyone who sees Kakadu in the wet, even from the air, understands why the seasons matter so much here.