On a flawless late spring morning last month, my husband, our two five-year-old boys, several friends and I boarded a boat destined for a deserted island. At 11:15 the ship's deep, loud whistle blew and the soaring rectangles of the skyline began to recede. We stood on the top deck with the wind blowing our hair, eager for our adventure. We arrived at our destination five minutes later.

When the offer came to ride the inaugural ferry to Governors Island, we jumped at the chance. The island has been mostly off limits to the public for more than 250 years. For many of us, the island just half a mile off the southern tip of Manhattan had loomed like a red apple dangling just beyond reach. "This is something that had always been in my peripheral vision," said Jonathan Levine, a member of our group who in the past had sailed near the island in his boat. "It was something so close, but you couldn't get to it." Now you can. Until September, ferries will run to Governors Island. (Call 212-514-8296 for information.) On Saturdays, visitors have access to the mile-long waterfront esplanade. Weekday visits will also include a one-and-a-half-hour tour. Two ballfields are open for the summer.

In spite of its name, the last Governor to reside on the island was the cross-dressing British Lord Cornbury in the early 1700s. During the Revolutionary War, colonial troops on the island defended New York from the British army. In the early 1800s, it came under the control of the federal government for military use and eventually became a Coast Guard base. It was abandoned by the Coast Guard in 1997 and has since remained empty and in disrepair. On Jan. 31, 2003, the island was returned to New York State for $1. Governors Island is shaped like an ice cream cone with the tip pointing toward New Jersey. Our visit began with a tour of the 70-acre national historic landmark district on the "scoop" side of the island. Our guide was Liam Strain, a burly park ranger whose previous assignment was fighting western forest fires. The National Park Service administers 22 of the island's 173 acres and there is a commitment to retain at least 40 acres as parkland. The tour's first stop was the massive Fort Jay, which dates from the 19th century. Two cast-iron cannons beside the fort point toward Lower Manhattan. Each has a range of two miles, enough to send a cannon ball to Washington Square Park. Around the bend, we were transported to a village ghost town, with only a sliver of skyscrapers visible in the distance to break the spell. We strolled down a wide paved lane under a canopy of tall elm trees, past graceful, large houses of red brick and pale yellow clapboard. How wonderful it would be, we imagined, to live in one of these houses with a backyard, a covered porch, no cars, and a five-minute ride to Lower Manhattan. But in a minute our fantasy bubble was burst. "Before everyone starts making their shopping list of which building they want to live in," Strain said, as though reading our minds, "the covenant that was part of the transfer documents forbade a number of things. One was casinos, another was private housing." The agreement does allow for overnight stays, opening the way for hotels, bed and breakfasts and college dorms. For now it is like an outdoor museum, not only of military history, but also of ordinary American life. When the island was last inhabited it had many of the amenities of late-20th century suburban life: a bowling alley, a movie theater, a beauty salon, tennis courts, three houses of worship, a nine-hole golf course and a Burger King (the only one that serves beer, we are told). Many of the 3,000 Coast Guard families lived in long buildings of garden apartments with great waterfront views. Our final stop was the circular courtyard inside the imposing, curved, 8-foot-thick red-stone walls of Castle Williams, which was built in 1850 and during the Civil War housed more than 1,300 Confederate prisoners in cramped and squalid cells. When the tour ended, at a grassy expanse along the water, there was delightfully nothing to do. We had a picnic with friends in the shade and then strolled along the esplanade enjoying the view of the Statue of Liberty, Ellis Island, the Brooklyn Bridge and the burgeoning New Jersey skyline. The harbor bustled with sailboats and tourist yachts. The wake from Staten Island ferries sprayed water up against the sea wall. At the far end of the walkway, we bought ice cream from a lone vendor and sat on the grass. It felt like a private park. My son, Nicholas, sprawled on his back as children do on warm, lazy days and closed his eyes to the sun. "We should have packed our things and moved here," he said. Instead, we reluctantly boarded the 4:30 ferry for home. "An island paradise in an asphalt jungle," a Coast Guard island resident wrote in the 1980s. In the coming years, decisions will be made about how the island will be used and what will be built there. Those decisions may determine if Governors Island remains paradise found or becomes paradise lost.