SYDNEY, AUSTRALIA -- Not since the days of Australia’s gold rush in the 1800s — and before that the dumping of 164,000 convicts unwanted by England — have so many passenger ships sailed toward the land Down Under. This time, the ships are westward bound for a different kind of gold: folding money from the purses of potential cruise passengers.

As big new vessels continue to pop out of shipyards, cruise lines are looking around the world for new customers to fill their ships. With European waters nearing a point of capacity, Australia is the next big thing.

Cruising is destined to become a major vacation business for the Aussies, and that also means new itineraries and adventures for travelers from North America to the South Pacific.

While most Australians never have vacationed on a ship, cruising is not new to this part of the world. Princess, Holland America, Royal Caribbean, Celebrity, and P&O have based a few ships in and around Sydney, mostly for short, seasonal stays. Vessels on round-the-world voyages annually stop in Australian harbors.

What’s new is the emphasis on drawing hundreds of thousands of Australians to sea. Their numbers have quadrupled since 2004, but the heavy battle for customers begins this fall, as nearly every North American cruise line is sending a big ship and/or increasing its presence with additional vessels, to establish a toehold.

Among the biggest ships headed westward are Royal Caribbean’s Voyager of the Seas (3,840 passengers) and Radiance of the Seas (2,112), Celebrity Solstice (2,850), Diamond Princess (2,670), Carnival Spirit (2,600), and Holland America’s Oosterdam (1,916). Other cruise ships in Australian waters this year include Sea Princess and Dawn Princess, Rhapsody of the Seas, Celebrity Millennium, Volendam, and P&O Australia’s Pacific Pearl, Pacific Jewel, and Pacific Dawn.

Ships are adding Australian meat pies, bacon, beer, and entertainment to make the Aussies feel at home.

“It’s going to be a dogfight,” said an executive at Holland America.

Which means that bargains will be available.

No matter what happens in rate wars, cruising in the South Pacific never will be an inexpensive proposition for North Americans, either in time or money.

Flights from the United States are long (12 hours-plus from the West Coast) and costly. Royal Caribbean, for instance, is advertising air rates for its passengers at about $2,000 from the United States to reach its ships for 14-day cruises out of Australia and New Zealand. If you want to spend several days in and around Sydney or Auckland — and you do — this trip takes a minimum of three weeks.

Cruise bargains, however, will start once you get to the South Pacific. Travelers with time on their hands could make a month of it, or more, with an eye on their budget, as cruise ship rates are lower than the cost of hotels and meals ashore, especially if you choose inside cabins. Perhaps, with all the ships to be based in Sydney, some North American travelers might pull a South Florida-style gambit, moving to Sydney for a while and cherry-picking cheap cruises as prices go down to fill the last cabins before a ship’s sailing.

Australian travel agents are promoting fares on North American ships as low as $100 a day per person for two people, on 2013 cruises booked now. Some of the older ships in Australia are countering with rates as low as $50 a day.