A total of 842 million international tourist arrivals were recorded last year, an increase of 4.5 percent, the Madrid-based World Tourism Organization said, citing preliminary data.
That followed a 5.5 percent jump in 2005. But such strong growth figures are expected to slip in the future, the agency said, citing possible energy tax increases imposed to fight global warming.
Rising interest rates in some countries, and the impact on household debt, could also take a toll, the report said.
Africa posted the biggest growth rate in 2006 at 8.1 percent, benefiting from travelers' fears of terrorism elsewhere in the world.
"Although no destination is immune to terrorist attacks, sub-Saharan Africa in particular is seen as being a long way from the center of zones of tension and unrest," the agency said in a report.
Africa is also a lure because of its natural resources, including wildlife, and appeal as a place for "authentic" experiences for vacationers, it added.
Europe and the Middle East both posted growth rates of 4 percent, while Asia and the Pacific saw an increase of 7.6 percent. This strong performance was due "in no small part" to the recovery of Thailand and the Maldives islands from the destruction caused by the December 2004 tsunami, and good showings by countries including Japan and China.
CBS News reporter Celia Hatton reports that China is poised to become the world's second most visited nation.
By 2010, the World Tourism Organization says China will eclipse Spain, drawing more tourists than any other country after the perennial favorite, France. Hatton says almost 50 million people visited China in 2006, making the Great Wall a very crowded wall as well.
The region with the weakest growth was the Americas — just 2 percent — due mainly to stagnation in arrivals in North America, the WTO said.
The cheaper U.S. dollar should in theory encourage travelers to head for the United States. But arrivals from western Europe, for instance, fell 3 percent.
Travel experts cited widespread confusion in long-haul markets over U.S. visa and passport requirements for foreign visitors, the WTO report said.
However, the United States remained the world's top tourism destination by revenue, followed by France and Spain.