KEY WEST, Fla. -- Looking dazed and sunburned, U.S. endurance swimmer Diana Nyad walked ashore Monday, becoming the first person to swim from Cuba to Florida without the help of a shark cage.The 64-year-old Nyad swam up to the beach just before 2 p.m. EDT, about 53 hours after starting her journey from Havana on Saturday. As she approached, spectators waded into waist-high water and surrounded her, taking pictures and cheering her on."I have three messages. One is, we should never, ever give up. Two is, you're never too old to chase your dream. Three is, it looks like a solitary sport, but it is a team," she said on the beach.