Rocksorts Inc., whose newest vacation destination, The Boulders, opens next month at Carefree, Ariz., is one of this country's most successful examples of how to blend a serious concern for conservation with a talent for designing resorts that attract tourists.

Certainly no other corporation has a top executive who can claim closer ties to the development of two U.S. national parks. And The Boulders is another example of Rockresorts' continuing efforts to make its properties compatible with the environment.

Laurance S. Rockefeller's six well-known, highly rated and distinctly styled Rockresorts will welcome the $50 million new member to the upscale "club" on Jan. 11 (it was originally scheduled to open before Christmas). The luxury resort is set at an altitude of 2,500 feet, 20 miles northeast of Phoenix, amid 1,300 acres of rugged desert country strewn with huge granite outcroppings, tall cacti and bright wildflowers.

Designed to resemble the natural rock formations and blend with its sunny surroundings, The Boulders will accommodate guests in 120 one-bedroom adobe casitas. Each is individually styled of wood and Mexican glazed tile and features a patio, a wood-burning fireplace and earth-tone furnishings. Indian handicrafts and original regional Indian artwork are displayed in the lobby of the main building.

The complex includes a 7,000-yard, 27-hole, par-72 championship golf course (with a 300-year-old saguaro cactus in the middle of one sand trap), six all-weather tennis courts, an outdoor pool and trails for horseback riding or hiking. Three one-bedroom "executive casitas" provide privacy for small executive meetings, in addition to the main facility for corporate sessions.

Daily rates through April 15 are $220 single, $270 double and $360 triple, including breakfast and dinner.

The new resort joins the Woodstock Inn & Resort in Woodstock, Vt.; Caneel Bay Plantation on St. John, U.S. Virgin Islands; Little Dix Bay Hotel on Virgin Gorda, British Virgin Islands; and the Grand Teton Lodge Company's Jackson Lake Lodge, Colter Bay Village and Jenny Lake Lodge -- all in Wyoming's Grand Teton National Park.

These resorts reflect a concern for both commercial viability and preservation of the environment; the goal in the design of each was to disturb nature as little as possible. Rockefeller, a millionaire industrialist, played an important role in the creation of conservation laws as chairman of the Outdoor Recreation Resources Commission under the Eisenhower and Kennedy administrations, and also served on conservation advisory councils under the Johnson and Nixon administrations.

All of the seven major resorts, and other related properties, are managed by Rockresorts, the New York-based management firm founded in 1966 by Rockefeller, who is its sole owner. The firm does not actually own any of the properties. The Boulders is owned entirely by local Arizona investors. Most of the other resorts are owned by two subsidiaries -- the Grand Teton Lodge Co. and the Caneel Bay Co. -- of a nonprofit conservation group, Jackson Hole Preserve Inc., whose chairman is Rockefeller. The subsidiaries also act as concessionaires for federally owned property within two national parks. (All profits from the two subsidiaries, and their resorts, are used to help defray operating expenses and support conservation work of Jackson Hole Preserve.)

The Rockefeller family's involvement with land preservation and recreational use dates back to 1926, when John D. Rockfeller Jr. and his wife, Abby, visited Wyoming's Jackson Hole area with sons Laurance, Winthrop and David. They noted the proliferating roadside stands, abandoned cabins and other disturbing signs of unplanned development and neglect. So John D. Rockefeller Jr. organized the Snake River Land Company, which quietly began to acquire private properties in Jackson Hole with the idea of donating them to the government for parks.

Grand Teton National Park was created in 1929, but at that time it consisted only of a portion of the mountain range and a narrow strip of the valley floor. In 1945, the Rockefeller lands were transferred to Jackson Hole Preserve Inc., and a few years later Laurance Rockefeller, as chairman of the preserve, gave the federal government 33,562 acres that were already protected by national monument status. Finally, in September 1950, the visionary plan of enlarging the park triumphed over its opponents, and President Truman signed legislation making the acreage part of the park.

By the early 1950s, the flow of visitors exceeded the capacity of existing facilities. So John D. Rockefeller Jr. provided funds to build Jackson Lake Lodge and improve Jenny Lake Lodge in an experiment that involved cooperation between government representatives and private commercial ventures in the park system. The Grand Teton Lodge Company today is the concessionaire that operates Jackson Lake and Jenny Lake Lodges and the Colter Bay Village camping center; it also owns and operates the Jackson Hole Golf and Tennis Club outside the park.

The Grand Teton properties, which close each September, will reopen between late May and early June. Rates are not yet listed.

Jackson Hole Preserve also played a major role in founding the Virgin Islands National Park and adjoining Caneel Bay Plantation. While cruising the Caribbean, Laurance Rockefeller discovered St. John and late in 1952 purchased a small Caneel Bay inn. Rockefeller and Jackson Hole Preserve again started acquiring land, and four years later more than 5,000 acres became the nucleus of the original U.S. Virgin Islands National Park.

Rockefeller donated his 178 acres of Caneel Bay land to Jackson Hole Preserve, which reopened the resort on a year-round basis in 1956. Caneel Bay opened this season with a $1 million refurbishment project that primarily involved the complete renovation of 20 tennis-garden and deluxe guest rooms. Daily rates to April 14 range from $245 to $380 single, $275 to $410 double, including three meals daily and activities.

Rockresorts is the concessionaire that operates the National Park's less-expensive Cinnamon Bay Campground, featuring tents and cottage units. Rates (double occupancy) through April range from $41 for tents to $50 for cottages.

Rockefeller, who also cruised to Little Dix Bay in the British Virgin Islands, decided in the early 1950s to develop a resort there. He acquired 142 acres of land, leased 365 more acres of adjoining land from the British government and opened the resort in 1964. Today the Little Dix Bay Hotel and the Virgin Gorda Yacht Harbor's sheltered anchorage a mile away are also managed by Rockresorts; they are the only resort properties directly owned by Rockefeller.

Rates at the hotel range from $250 to $285 per person double, with three meals daily, and include the use of tennis courts, small sailboats, bikes and snorkeling gear; water-skiing; boat taxis to other beaches; and free transportation from Virgin Gorda airport. Packages are also available at both Caneel and Little Dix.

In 1969, the Woodstock Resort Corp., another Rockefeller firm, built the Woodstock Inn & Resort on the village green in the center of the Vermont town. The foothills of the Green Mountains run alongside the golf course, which in winter is transformed into a cross-country ski area. This season, in celebration of its 15th anniversary, the inn is offering guests free skiing -- rentals, lift tickets and trail passes -- at both the Woodstock Ski Touring Center and the Suicide Six downhill ski area (Monday through Friday, but excluding the Washington and Lincoln birthday holidays). Rates through May 10 range from $78 to $115 double, without meals.

For reservations at any of the Rockresorts, concessions or related properties, phone (800) 223-7637, or see a travel agent.