A combination of September 11 and the state of the US economy has produced a 17 per cent drop in the number of Americans visiting Switzerland.
Swiss Tourism has launched a major campaign to buck the trend.
In terms of overnight stays in Swiss hotels, the Americans have traditionally come second only to the Germans.
Since September 11, though, they have slipped to third place, behind the British.
Americans tend to outspend their European counterparts. On average a US tourist spends SFr330 ($222) a day when holidaying in the Land of Mountains, as Swiss Tourism markets it.
Switzerland usually welcomes around a million visitors from the United States every year.
But in the first six months of 2002, there has been a fall of 17 per cent. The figure for the whole year is expected to be around 15 per cent.
"It's a dramatic decrease if seen in absolute terms. It works out at around 160,000 people. If you multiply that by 330 francs a day, that's quite a lot of money," says Urs Eberhard, director of Swiss Tourism North America
From his office overlooking New York's Fifth Avenue, Eberhard is the man responsible for maintaining American interest in Switzerland.
And recently he has had his work cut out. Swiss Tourism has launched a publicity campaign to remind Americans of Switzerland's attributes
"We have decided to adopt a very pro-active strategy," Eberhard told swissinfo.
Swiss Tourism has hired more people so that contacts with influential groups like tour operators and journalists can be stepped up. Partnerships have been forged with holiday web portals.
"If people do not want to come, we cannot force them," says Eberhard. "But we are investing in the market at a time when a lot of our competitors are not investing."
"By keeping Switzerland at the forefront of people's minds, we believe that when the market does improve again, we'll be in pole position," he adds.
The reasons why Americans are not travelling in such great numbers are many and varied.
In addition to the fears provoked by the events of September 11, the main one is probably the slump in the American economy and the resultant fall in share prices.
With people fearing for their pensions, they are less likely to splash out on a foreign vacation.
Eberhard believes recent events in Switzerland - notably the collapse of Swissair and the fatal crash in the Gotthard road tunnel - have not played a part in dissuading people from travelling, even though they may have dented Switzerland's image abroad.
However, the Swissair debacle and September 11 have resulted in a substantially reduced transatlantic airline capacity.
"Compared with a year ago, there are 127,000 seats less every week," says Eberhard.
"We have lost 30 per cent of the capacity between the United States and Switzerland. Capacity is lower, so prices are higher."
All these factors - the economy, high prices, fear of terrorism - have also combined to affect the number of tourists travelling in the opposite direction.
"There are definitely fewer Swiss - and Europeans in general - coming to the United States," he says.
swissinfo, Roy Probert in New York
17 per cent fall in US tourists to Switzerland during first half.
Transatlantic capacity drops by 30 per cent.
Experts blame September 11 and US economic downturn.
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