Tortola -- like many islands in the Caribbean -- straddles the line between preservation and development, and does it gracefully. Its two highest peaks exemplify the conflict: One is a national park with traces of a primeval rain forest; at the apex of the other is a stylish restaurant offering nouvelle cuisine, espresso and a panoramic view.

Tortola is the most populated island in the British Virgins, yet not many people have heard of it. Travel agents often focus on the rain forest, and one recently said, "There's not much happening on Tortola. It's all natives, boat people and beaches." In fact, development has come only recently, and in a limited and controlled fashion.

You don't go to Tortola looking for trendy shops, nightclubs or constant attention. You go there because it's a lovely place to visit, because there's a certain balance on Tortola and a wide range of choices. The oceangoing activities are ever-present, of course -- you can sail, fish, dive, snorkel or bathe at deserted beaches (or crowded ones, if you prefer). But you can also tour by car or boat, and have a better-than-average meal at a different restaurant every night.

At the center of the Sir Francis Drake Channel and in the cluster of the Eleven Thousand Virgins (as Columbus christened these northwesternmost Lesser Antilles), Tortola has a definite seagoing air about it. "Bare boating," the chartering of yachts without skippers, makes up more than half of the BVI tourist trade. There are always dozens of boats in sight sailing among the islands, yet Tortola is also appealing to landlubbers who would rather stare at boats while firmly anchored on a beach chair.

Tortola covers about 35 square miles and is linked to Beef Island by the tiny -- and perhaps the world's least expensive -- toll bridge. Beef Island, once a great hunting ground, is now home to the BVIs' largest airport. Though the airport is scheduled for upgrading, there are no plans to land jumbo jets anywhere in the BVIs. But the locals see the restaurant on the peak, the hotels on the beaches, the yachts in the harbor and fear for the island's future. And this fear of mass tourism isn't hard to justify.

Just a one-hour ferry ride from Tortola lies the relatively urban U.S. Virgin Island of St. Thomas, which, to Tortolans, provides an example of tourism run rampant.

"Do you realize," asks Cyril Romney, the chief minister of the self-administered island chain, with a certain amount of horror in his voice, "that over 250 million people have unlimited access to the U.S. Virgin Islands?" Romney and many other Tortolans believe it is this unrestricted access to the American islands that has led to the chain's overdevelopment and associated problems.

Even Britons and residents of British-associated islands such as Antigua and St. Kitts must be cleared through Tortolan customs before they can spend any time in the BVIs. And the immigration laws are strictly administered, resulting in an unemployment rate that approaches zero, according to government figures.

Tourism in the BVIs is only 20 years old. Little Dix Bay Hotel, built by the Rockefellers on Virgin Gorda in 1963, was the first of a few big projects. The founding of two boat charter companies followed soon after, quickly making Road Town, Tortola's main harbor and capital, the Caribbean's center for bare boating.

"Because tourism in the BVIs began with big projects that had a deliberately long time frame for recovering investments," says Romney, "the get-rich-quick speculators were forced to go elsewhere. And we were presented with a de facto 'high quality tourism' here, which we intend to keep."

Most Tortolans realize the need for tourism -- it has rapidly become the island's largest industry -- but, at the same time, there's a demand for preservation and for respect between tourist and native.

Most Saturday mornings, even at the height of the season, a local Boy Scout group works out in the pool at Prospect Reef. This is Tortola's largest hotel, with 130 rooms just outside Road Town. Its general manager is Jim St. John, who defends the pool-sharing, even though it obviously distresses some guests: "I don't want Tortolan kids growing up feeling like tourism deprives them of anything; that's not altruism, just good business. There needs to be a balance, and it's important to keep the sense that the island belongs not to tourists but to the people who live here."

You get that sense here; Tortola could lay claim to the Jamaican slogan, "We're more than an island, we're a country." Tourism is welcome, encouraged, essential, but it's not all-powerful. Only one or two cruise ships stop in port each week, and frequently the passengers on shore excursions find Road Town shut up tight -- the desire for peace and quiet having outweighed greed and "good business sense." There are no huge hotels, gambling casinos, armed police or 15-foot fences here. The government offices, in a three-story building, constitute Road Town's most impressive structure.

Just 20 years ago, Tortola was served by a weekly plane from Antigua; there was no road system or mass electrification. ("I remember the days when you could name everyone here who owned a car," mused one middle-aged Tortolan. "There were about 35 of them in the early '60s.")

Now, Road Town seems much like a county seat in rural New York or Pennsylvania, with the air of a vital market center. It is the place to go shopping -- not for bargains or gifts (nearby St. Thomas still gets most of that traffic) but for food. Most hotels offer rooms with kitchenettes: Prospect Reef equips two-thirds of its rooms with refrigerator, sink and stove, and some of the island's smaller hotels have cooking facilities in their rooms. This -- combined with off-season room rates that frequently are a third to a half lower than in the winter months, and discounted plane fares -- can make for an inexpensive summer visit.

It's easy to get around Tortola, and it's easy to get away from it. "Most of the people who come here for a week rent a car for a day or two and then take an off-island day-trip," says Jim St. John of Prospect Reef. "St. Thomas and St. John are both popular," the first for shopping, the second for isolation.

We recommend the 40-minute ferry ride to Virgin Gorda -- with 2,000 people, the second most populated island in the BVIs -- for a visit to The Baths. These are not hot springs and spas, but sea pools and caves formed by boulders, some of them 20 feet and more in diameter. They can be explored for hours: walking, swimming and climbing in, out and through the rock formations. By far the most popular tourist attraction on Virgin Gorda, The Baths reach their saturation point in season; last January there were lines waiting to get through the small, cavernous passageway that leads to the main sea pool. But by April things had quieted down again, and at that time of year visitors will be few.

Although Tortola has nothing quite so spectacular, once out of Road Town there is a quiet ambient beauty that makes every drive delightful (despite the constant need for the warning, "Drive on the left . . . "). Directions are frequently given by hill -- as in, "We're the third small road on the right after you get to the crest of the fourth hill," which gives some indication of the kind of driving you do here. The main geographic feature is the island's mountainous spine, dividing Tortola neatly in half.

From nearly everywhere on Tortola you can see other islands in the area. After a few days of motoring in the hills, you get to know them by sight and by name: Salt Island, whose 10 or 12 remaining inhabitants still pay the British crown an annual rent of 52 pounds of salt; Jost Van Dyke and Guana islands, each with a resort for people looking for real solitude; the unfortunately named Mosquito Island -- which has a small hotel -- and its equally attractive-sounding partner, Cockroach; the familiar Peter Island, whose hotel and harbor lie directly across from Road Town; and, a personal favorite, The Indians, some sticks of stone off Norman Island that do resemble a group of humans.

It's worth considering staying on the Road Town -- that is, south -- side of the island, for the sake of convenience. This is the sole place on Tortola where hotels, restaurants and stores are within walking distance. Only here can you snack on a freshly made piece of coconut bread while browsing through the fine bookstore.

There is good snorkeling right off the south side's rock shore, and for divers, boat lovers and island-hoppers, proximity to the Sir Francis Drake Channel is a must. The wreck of the Rhone, a veritable shrine for scuba enthusiasts, is a quick boat ride away. (Here, too, winter visits are hectic and crowded; the Rhone is becoming the first underwater marine park to be littered. Consequently, an off-season dive has added appeal.) And day-trips that combine sailing, picnicking and snorkeling are provided by some hotels for little or no cost. These go to places like Peter Island -- which has a luxury hotel and some lovely, deserted beaches -- or to Norman Island, where you can snorkel through the splendid offshore caves.

But Tortola's rocky south shore -- oriented as it is toward boats and divers -- will frustrate beachcombers. And those who make a priority of spending hours each day lying on long stretches of sand, those who want to sit alone on a rock and watch the pelicans work their territory and others who want to get a feel for the rural life of a Caribbean island should consider the less-populated north shore.

Driving over the central ridge is an activity in itself: The hills are terraced, with cattle and goats grazing in unlikely spots, and the views are spectacular (on a clear day you can see Puerto Rico, about 50 miles away). The north shore is dotted with settlements, one to each bay: There are schools, churches, restaurants and bars, but no markets or stores of any kind. The hotels are quiet, modest and pretty.

The island's best restaurant is here, at Sugar Mill Estate, an old hotel recently purchased by two American food writers. Their $17.50 prix fixe meal, featuring a menu that changes nightly, would be a bargain anywhere. And the meal includes the only decent salad we've eaten on Tortola (the owners tend a small garden). Ironically, Mrs. Scatleff's restaurant -- just down the road and as authentic as you can get -- is more expensive. Mrs. Scatleff has developed a following based on her fine handling of local ingredients -- including conch, soursop (a fruit) and a variety of native fish and meat.

The north side's trump card is its endless series of bays and beaches, all facing the majestic Atlantic, with nothing between here and Bermuda except the isolated and virtually invisible Anegada, 20 miles away and flatter than Kansas.

The graceful and aptly named Long Bay is popular with surfers and makes an ideal jogging spot. All tourists who rent cars and seem adventuresome are sent to the empty beach at Smuggler's Cove. Finding this takes some courage and patience, due to the tortuous dirt road leading there, but most people make it and are gratified. (Once there, you may be tempted by the somewhat rundown but indisputably isolated Smugglers Cove hotel.) Cane Garden Bay is one of the largest and most popular beaches on the island; it's especially worth a trip on Sunday, when Tortolans gather for picnics, music and dancing.

The search for the ultimate beach is endless here, since each seems more spectacular than the last. The closest to our dreams is at Josiahs Bay: a classic crescent, with ends defined by boulder-strewn, sage-scented hills. There is no reef, so the waves come in rhythmically and well-formed, breaking on the pristine sand.

Since builders have removed some of the fine sand for cement, there's a caretaker at Josiahs Bay, a man who sits in the shade (yes, there's plenty of that, too) and protects the beach. He says there are bigger, prettier and less-crowded beaches (this was said with a straight face, although there were only five people at Josiah's at the time) just to the east. Those will be our first stop the next time we're in Tortola.