The boat looked as big as an apartment building. It was 80 feet long, white as Ahab's whale and rose three stories out of the water. It made the armada of sailboats berthed around it in this tiny harbor seem perilously frail, especially after it ran aground on a sandbar, then began revving its 60 gallons-per-hour engines trying to get free.

"You cut my anchor line!" screamed one sailor after the boat crossed his bow. A dozen other captains stood on their decks, watching the meandering voyage of the huge boat the way parents might watch a sea monster swimming toward their child.

"I just love to sit here and look at people dock their boats," said John Chandler, a NASA engineer from Bowie who was docked far enough away from the marauding boat to enjoy the show. "There is always something to look at here."

On weekends, when the weather is fair, the Chesapeake Bay loses its green horizon to thousands of multicolored sails. Schooners, sloops, ketches and even a few Chinese junks sail out of harbors to ride the wind and get in right-of-way disputes with power boats and fishing vessels from Baltimore to the bay's mouth near Virginia Beach.

If crowds are what you seek, there are ports beside the Chesapeake you can almost cross by hopping from one deck to another. But the bay is also big enough to provide escape.

"There are so many creeks and rivers, so many places to go, you can go a whole weekend and never see another boat," said Chandler, who spends almost every weekend from early spring to late fall with his wife Carolyn on their 33-foot sloop Spirit.

This weekend, the Chandlers joined the crowd at the St. Michael's Maritime Museum. This 17-year-old museum on the bay is dedicated to preserving and displaying the old work boats that are indigenous to the Chesapeake, such as skipjacks, oyster sloops, bugeyes and log canoes. It is no small irony that many of the museum's 80,000 to 100,000 visitors arrive on fiberglass pleasure boats that have now laid claim, at least in number, to the bay.

"You wouldn't know the economy's dead by the number of those I've seen this year," said Leigh Scott, who was on board Chandler's sloop watching the big boat run aground and finally escape the narrow harbor.

Scott is a 31-year-old native of St. Michael's and one of a very few women skipjack captains. Skipjacks are sailing ships used to dredge the bottom of the bay for oysters during the winter season. The work is hard under the best of conditions. Scott and the Chandlers are a perfect parallel to the contrast between the museum pieces and the people who come to view them.

"She has to know what she's doing on the water," said John Chandler. "We pleasure boaters sometimes know what we're doing."

Leigh Scott grew up on the land that is now the museum. Her former home is now a fancy restaurant. Her mother's riding stable is now a cocktail lounge. Her grandparents still live on a piece of the land, separated from the tourist traffic by a corn field.

"Fifteen years ago, before the tourists started coming here, this was just a small waterman's town," said Scott, who has watched the arrival of the antique shops and the polished brass with mixed emotions.

"I know it's good for the local economy," said Scott, who recently married a sculptor from Chicago. "I just don't like waiting in line an hour for groceries."

One of the more interesting pitches to the boating crowd has been made by the Wye Mills Theatre. This dinner theater, which sits near the Wye River and operates during the spring and summer, depends on the boating community for about 15 percent of its audience.

"Three years ago a woman from the State Department wrote me to say she was sailing down and suggested I pick her up at Wye Landing," said Joan Kramer, who started the theater seven years ago in two tents beside a cornfield. "It sounded like a great idea, so we started advertising. This year the word has really gotten out and people know about it."

Saturday night 70 people, most on sailboats, came up the Wye River to eat dinner and see "Sleuth."

"You see every aspect of the Eastern Shore on the Wye River," said Renee O'Bannon of Annapolis. "There are quiet little creeks and coves and beautiful estates."

She and her husband Bill have been sailing to the theater from Annapolis for the last three years. To hear Kramer talk about them, you would think they had descended from some ethereal plane.

"I've never seen a boater I didn't like. They are always so good-humored," said Kramer. "You can tell they've been floating around on water for a while, they look a little spaced-out."