Before my daughter and I even boarded the plane to Nantucket from Boston, I began to wonder what I'd gotten us into. Other women awaiting the flight to the island 30 miles off Cape Cod wore Gucci flip-flops, Lilly Pulitzer clamdiggers and diamonds the size of golf balls. A tanned man in a stylishly rumpled linen jacket worked his iPad from behind sunglasses. Then, when our 30-minute flight touched down, we rolled past a long row of private jets parked near the tarmac. They seemed to turn their noses up at us.

The next day, all of that swank faded into the background as we biked to the beach across a landscape of sand dunes and salt marshes.

It's true that Nantucket's real estate market is the most expensive in Massachusetts; a nine-bedroom oceanfront home recently went for $25 million. We didn't dwell on that as we zipped past gray shingle-sided cottages ringed with roses and skirted nature preserves. What struck me most was not the wealth, but the timeless, weathered beauty of the place.

The entire island is a national historic landmark district. Benjamin Franklin's mother began life here, Herman Melville wrote about it in "Moby Dick," and 18th- and 19th-century mansions line the streets of town. Also, 50 percent of the land is protected, including sand dunes, grasslands and wetlands. In this rare and storied air, we had a great time — and we didn't break the bank.

For that, we can thank our cabdriver who, in a place filled with laconic locals, was remarkably helpful, even friendly. As she drove us from the airport to our hotel, she gave us key insider tips for our 24-hour trip.

Get ice cream at the Juice Bar. "Bill Murray came in when I worked there," she said.

Rent bikes from Young's Bicycle Shop, which "has been around forever," she advised. (For the record, that means since the 1930s; I asked at the shop.) The other bike place, two doors down, opened in the 1980s; in a town settled before the Civil War, that makes it a relative newcomer. "Pariahs," she called them.

Eat lunch at Yummy, right off a bike path, she said.

That night after dinner, we strolled around town, where there is so much money to be spent that stores stay open until 10 p.m. to collect it. In the Jack Willis shop (think Ralph Lauren, but British), I watched a young girl wearing a Juilliard T-shirt stomp in, look around, put her hand on her hip and loudly ask her mother, "Where's the kids' section? That's what I want to know."(There was none.) When another mother-daughter duo bickered extravagantly over a credit card, I decided it was time to find the happy people.

We joined the line out the door at the Juice Bar, where the mood was full of summertime cheer and the ice cream was uber-rich — maybe a bit like the people waiting in line with us, though who could say when a scoop is $4.

The next morning, we rented bikes, decided what kind of waves to face and headed to the beach. With 82 miles of coastline and more than 30 miles of bike paths, we had options.

We chose Cisco Beach for its Atlantic rollers, and veered off the bike path at Yummy.

As we sat in the shade of an umbrella eating a delicious salad topped with crispy falafel and juicy island-grown tomatoes, a man wearing paint-splattered pants ordered at the counter. A dented truck pulled up, and a trio of gardeners tumbled out. Our cabdriver had steered us to the affordable locals' lunch spot.

At the beach, about 4 miles out of town, we locked up the bikes, grabbed our beach towels and rushed down the sand dune to the crashing ocean. For a few sweet hours, we floated in the swells and let the waves push us back to shore, where we soaked up the sun. Eventually, reluctantly, we pedaled back to town.

A few hours later, the tiny airport was overflowing with the Gucci set because an East Coast storm had delayed planes out of New York and other points west. James Carville, a television staple during the Clinton years and our own minor celebrity sighting, worked the room, gregarious even as he lamented the disruption.

Amid the chaos, we heard our names being called. The small plane that would take us back to Boston was one of the few to fly that evening. Like Nantucket's wild natural beauty, the skies held no hierarchy of vacationers.

As we took off, I noticed sand in my hair. It was my own free island souvenir.

Kerri Westenberg • 612-673-4282