By Tom Brown

MIAMI (Reuters) - Veteran long-distance swimmer Diana Nyad reached dry land on Tuesday, although not the way she had hoped after giving up on her fourth and possibly final attempt to make the 103-mile (166-km) swim from Cuba to the United States.

The 62-year-old American, who battled squalls, rough seas and jellyfish, had set out from Cuba on Saturday to cross the Florida Straits. Nyad spent more than 50 hours in the water before she abandoned the swim.

"Should I say I'm not disappointed? No, I am disappointed," an exhausted-looking Nyad told reporters after arriving in Key West with her support team.

"This is my dream, my passion," she said standing on the beach where she had hoped to make a triumphant arrival a day before her 63rd birthday. "I didn't get my own moment in history but this has been a terrific experience."

If Nyad had completed the swim, she would have owned the world record for the longest unassisted open ocean swim, which means without a shark cage. Instead of a cage, equipment emitting a mild electric current in the water kept sharks at bay during most of her swim.

Mark Sollinger, a leader of the team accompanying Nyad in five boats as she attempted the crossing, told CNN a powerful and "extremely difficult Gulf Stream" had pushed her badly off course.

When she gave up, Nyad was a point that would have required her to swim another 28 to 40 hours to complete the crossing, Sollinger said.

He did not give the exact time or location when Nyad was pulled from the water but those details were expected to be announced later.

Nyad said it was a hard decision to give up after her support team advised her to abandon the feat. "They saw the jellyfish and the trouble I was having going through them," she said.

THE DREAM

Nyad told reporters in Havana last week that she hoped her swim would inspire people her age to continue pursuing their dreams.

"Instead of staying on the couch for a lifetime and letting this precious time go by, why not be bold, be fiercely bold and go out and chase your dreams?" said Nyad, who left competitive swimming 30 years ago and has since worked in television and radio and as a motivational speaker.

She also hoped the swim would help U.S.-Cuba relations, which have been sour since the Caribbean island's 1959 revolution.

The Cuba-U.S. swim has only been completed once. Australian Susan Maroney was 22 and used a shark cage when she made the crossing in May 1997.

Nyad has now tried to make the swim four times, including twice last year, but never got much more than halfway before she had to give up.

Asked before this latest attempt if it would be her last, Nyad said: "This has to be it, it just has to be."

She sounded a less sure note on Tuesday after reaching Key West. "I don't have an answer for that," she said when asked if she would try again. "I'm too busy considering what's happened today."

Waves and stiff winds derailed her first try in 1978, when she was at the peak of her swimming career. Three years before that she swam around Manhattan in under eight hours and, in 1979, she made the 102.5-mile crossing (165-km) from Bimini to Florida.

Nyad's latest swim followed that of Penny Palfrey, a British-born 49-year-old grandmother from Australia, who tried the Cuba-Florida crossing in late June and swam 93 miles before the Gulf Stream forced her to stop.

Palfrey holds the record for the longest unassisted swim, 67.5 miles in the Cayman Islands last summer.

(This story is corrected with quote in fourth paragraph to read "this has been" instead of "that has been")

(Additional reporting by Jeff Franks in Havana and Michael Haskins in Key West; Editing by David Adams and Bill Trott)