Planning a summer vacation takes time, so it's not surprising that many busy people find themselves approaching midsummer without any idea how to spend their holiday.

They know they want to get away. But where?

With that in mind, we've put together a list of tempting possibilities available now through autumn -- for a week or two, or just a long weekend. The trips range in price from budget to luxury. Some are escorted tours, others do-it-yourself vacations.

You can go camping in Alaska, snorkeling in the Caribbean or on an art tour of Spain. You may choose to explore the old Silk Route of China, canoe in the Adirondacks, trace Civil War history outside Washington or sample the comforts of fine Canadian inns. Among the choices:

The romance of a Canadian inn: France was the birthplace of the association of small hotels called "Relais & Chateaux," and in that nation of gourmet delights its members are well-known for the quality of dining and lodging they provide. Ten Canadian inns are now a part of the organization, selected for their comfort and cuisine. Nine are scattered along the St. Lawrence River and the eastern Great Lakes; the tenth is on an island in western British Columbia.

Travelers might go for a weekend stay at the eastern Relais & Chateaux, flying to Quebec, Montreal or Toronto. Or they could stretch their getaway into a driving trip for a week or more through the St. Lawrence region, stopping at several of them.

With the favorable exchange rate, prices for the special charms of a Canadian inn are reasonable. At La Pinsonnie`re Cap a` l'Aigle in the province of Quebec, a room for two people (with breakfast, dinner, tax and service charge included) begins at $165 Canadian (about $110 U.S.). The best rooms, with canopied beds and fireplaces, are $235 Canadian a day per couple, or about $157 U.S.

Typical of other Relais & Chateaux, the small inn has only 24 rooms. Now 9 years old, it occupies a former mansion that overlooks the St. Lawrence about 75 miles downriver from Quebec City. Amenities include an indoor swimming pool, tennis court and nearby golf.

For a brochure describing the 10 inns, contact: Relais & Chateaux Canada, P.O. Box 131, 260 Adelaide St. East, Toronto, Ontario M5A 1NO, Canada, (416) 361-0544. For reservations at La Pinsonnie`re, (418) 665-4431. The Caribbean off-season: Many vacationers are discovering the unhurried pleasures of a Caribbean summer. The crowds are gone, but the sand and the sun and the sea remain. Better yet, lodging prices drop considerably.

For example, on the tiny, very fashionable French island of Saint Barthe'le'my (St. Barts), the new Guanahani resort hotel is advertising a summer rate beginning at $160 a day per couple. The winter rate, by comparison, begins at $250 a day. The price includes service charge and transfer from the airport.

A special three-night package called "Le Weekender" -- room, daily continental breakfast, a candlelight dinner for two one night, a champagne welcome -- is $275 per person (double occupancy).

Each of the hotel's 80 rooms has either a patio or a balcony, and all have at least an ocean view, although more expensive rooms front the ocean. The hotel has a beach, swimming pool, two tennis courts and two restaurants. St. Barts is reached by connecting flights from the nearby island of St. Martin.

For reservations: First Resort Corp., 307 E. 56th St., New York, N.Y. 10022, (800) 235-3505 or (212) 308-3330. Spain for students of art: This two-week tour in October focuses on the modern art of Spain as represented primarily in the Costa Brava city of Barcelona and in Madrid. It is sponsored by the Friends of the Philadelphia Museum of Art.

Barcelona "has been enriched by the new and vibrant energy of artists such as Picasso, Miro, Dali and Gaudi," according to a tour description prepared by the organization. A side trip is planned to Salvador Dali's home near Cadaques, and special programs include visits to private museums and private dinners with leading members of the art circles in Barcelona and Madrid.

Departure is Oct. 4 from Philadelphia. The price is $3,195 per person, which includes round-trip air fare, lodging, some meals and a $200 tax deductible donation to the museum.

For information: Travel, The Friends of the Philadelphia Museum of Art, P.O. Box 7646, Philadelphia, Pa. 19101-7646, (215) 787-5496. (Phone Tuesday through Friday, 10 a.m. to 5 p.m.) An American history lesson: If you don't want to wander far from home on a vacation, consider an eight-day tour of "The Eastern Battlefields" of the Civil War, which swept the countryside outside Washington in brutal fury.

Certainly you can plot an itinerary of your own, but Jameson Travel of Beverly Farms, Mass., which specializes in historical tours, has put together an escorted trip that departs Washington for many nearby battlefield parks.

With historian John Hennessey, author of a tactical study of the Second Battle of Manassas, the group will visit such noted Civil War battle sites in Virginia as Manassas, Fredericksburg, Chancellorsville, the Wilderness, Spotsylvania, Richmond, Petersburg, Appomattox, New Market and Winchester as well as Antietam in Maryland.

Accommodations are in the Sheraton Inn in Fredericksburg, the John Marshall Hotel in Richmond, the Hilton Inn in Lynchburg and the New Market Quality Inn in the Shenandoah Valley. Departure is Oct. 10. The price is $959 per person (double occupancy) and includes eight nights' lodging, seven dinners, seven lunches, two receptions and all touring.

For information: Great Journeys by Jameson Travel, P.O. Box 484, Beverly Farms, Mass. 01915, (800) 225-2553 or (617) 922-0577. The Adirondacks by canoe: Your base camp is a small, comfortable backwoods lodge in the Adirondack Mountains of New York. Each day for a week, guides lead you and other guests -- no more than 14 at a time -- in exploring the surrounding woods, lakes and streams by canoe.

It is "total immersion in the Adirondacks," says Richard Beamish of Adirondack Wilderness Tours. By this he means that participants begin their day with "a lumberjack breakfast"; cover perhaps 8 to 12 miles by late afternoon (with some side trips on foot); share a picnic along the way; and return to the lodge for a buffet dinner. Evening entertainment features talks and slide shows on Adirondack history and ecology, folk singing and square dancing. At least one staff member plays banjo.

The lodge, built of logs, sits on the forested shoreline of McCauley Pond, which is home also to families of otters, beavers and muskrats. The living room has a large stone fireplace, and there are five double bedrooms with shared bath. A nearby cabin sleeps four. Smoking is not permitted inside the lodge. A sauna helps ease aching muscles.

Each week's program begins Saturday afternoon and runs through breakfast the following Friday. Canoe weeks are scheduled beginning July 4, July 18, Aug. 1, Aug. 15, Aug. 29 and Sept. 12. Two fall weeks are planned for hikers, beginning Sept. 26 and Oct. 10. The all-inclusive price is $550 per person.

For information: Adirondack Wilderness Tours, McMaster Road, Saranac Lake, N.Y. 12983, (518) 891-1080. The arts of New Hampshire: This is a do-it-yourself holiday. You roam at your own pace, visiting as many of the state's nearly 100 museums, galleries, craft shops and studios as you choose.

Your guide is a colorful new Visual Arts Map brochure describing -- and locating -- these sites. It is distributed by the League of New Hampshire Craftsmen Foundation.

A trip could take you to the coast or into the mountains. You may want to stay someplace different each evening or settle in at an inn, a grand old hotel such as the Balsams in Dixville, or a sports resort. The map will direct you to boat builders, potters, silversmiths and painters.

In Canterbury, there's an acre of herb gardens at the Heritage Herb and Baskets shop. In Wolfeboro, visitors can watch workers cast pewter at the Hampshire Pewter Co. Handmade kaleidoscopes are sold at the Salamandra Glass Studio and Gallery in Portsmouth. The Cordwainers in Deerfield fits you for custom-made shoes. The state's crafts will be celebrated at the 54th Annual Craftsmen's Fair, Aug. 1 to 9, at Mount Sunapee State Park in Newbury.

To obtain a copy of the Visual Arts Map, send a stamped, self-addressed, business-size envelope to the League of New Hampshire Craftsmen Foundation, 205-Z North Main St., Concord, N.H. 03301. For information about the fair, (603) 224-1471. Along China's Silk Route: Sponsored by the Denver Art Museum, this three-week visit to Old China will be led by the museum's assistant curator of Asian art, Julia White. She will provide detailed background information on the sites to be visited.

The itinerary begins in Beijing with visits to the Imperial Palace and the Great Wall of China. It continues on to Datong, where the attraction is the Buddhist caves featuring early examples of stone-carved temples. Next stop is Urumqi, the capital of remote Xinjiang Province and home to many tribal cultures. Other stops are the mosque-filled city of Kashgar and its medieval Sunday market; the oasis town of Turfan; Dunhuang for its eight-story-high Mugao Caves; and Xi'an for its life-size terra cotta army. A boat ride down the Yellow River leads to early Buddhist caves at Binglingsi.

The trip is limited to 15 persons, departing Sept. 4. The price is $4,299 per person, which includes air fare, accommodations, all meals in China and a $200 donation to the Denver Art Museum.

For information: Sara Qua, Membership Department, Denver Art Museum, 100 W. 14th Avenue Parkway, Denver, Colo. 80204-2788, (303) 575-2481. The Pacific Northwest by small van: A new Oregon firm, Personalized Tours & Travel of Portland, has put together a program of nine excursions by van into the diverse scenery of Oregon, Washington, British Columbia and parts of adjacent states and provinces. The group size is kept to no more than 12 for flexibility and congeniality.

You can opt for a camping trip (cheaper) or sign up for one that provides a nightly roof over your head. Trips are either eight days or 15 days, and they will take you high into the Cascade and Rocky mountains, down the beautiful Oregon coast and into desert country.

Among the itineraries is the eight-day "Washington Getaway." Departing Portland at least twice a month through October, it explores Mount St. Helens, Mount Rainier National Park, the alpine resort of Lake Wenatchee and Whidbey Island on Puget Sound. Along the way, there will be time for hiking, visiting wineries, boating and riding whitewater rapids in a rubber raft.

The price for a camping trip is $380 from Portland. Participants contribute about $5 a day for meals. A trip with accommodations is $480. All meals are extra.

For information: Personalized Tours & Travel, P.O. Box 17513, Portland, Ore. 97217, (800) 248-0414 or (503) 248-0414.