Londonderry is to host the 2011-2012 leg of the Clipper round-the-world yacht race.
Derry City Council announced on Monday that the city will be an official host port welcoming the fleet in July 2012, after the final transatlantic stage of the 40,000 mile race.
There will also be an official Derry yacht in the race, which will take in 15 ports on six continents.
Mayor Colm Eastwood said he expects the event to bring £6m into the local economy.
Mr Eastwood said the event was "tremendously significant" for the city.
"We're talking about 100,000 visitors plus on the weekend when they're here.
"We're also talking about ten months when Derry can promote itself around the world at every one of the places where the yachts dock," he said.
The Clipper Race, which is the longest ocean race in the world, was set up by Sir Robin Knox-Johnston, the first man to sail solo, non-stop around the world.
It was designed to give ordinary people with no sailing experience a taste of adventure.
The teams will be made up of people from all walks of life and organisers hope that local men and women will also be inspired to get on board and represent their city on a global stage.