Harry Cohn knows he's not conquering Mount Everest, but the 75-year-old New Yorker takes every chance he can get to bust out of familiar surroundings and see the world.

Peru, Bolivia, Easter Island and Costa Rica are among his favorite destinations. He has visited and revisited all of them over the past several years.

Cohn is one of numerous seniors who seek spice in their travel. And as the baby-boomers pass 50, they're creating a larger adventure-vacation market because they're better off both financially and physically than previous generations.

If you fit this niche and want to do more than pack a swimsuit and a thick novel, here are suggestions for taking the more adventurous route.

If you're interested in outdoor adventure, there are a number of outfits that may not cater specifically to seniors, but certainly include them among their most devoted customers.

Among them are Adventure Specialists, (719) 783-2519, which focuses on Spain, Peru, Mexico and Colorado; and Nature Expeditions International, (800) 869-0639, which plans trips to 35 spots on all seven continents.

Cohn has long traveled through Nature Expeditions International. His last trip took him to Copper Canyon in Mexico, then to the Pacific Coast where he boarded a small vessel that sailed down to Costa Rica, through the Panama Canal and to islands on the east coast of Panama.

He and his companions took canoes up the rivers there to visit interior residents.

Cohn's biggest adventure in recent years took place on Chile's Easter Island.

"I got to explore the ancient stonework, sleep in [explorer] Thor Heyerdahl's room and I wrote up all my notes on Heyerdahl's desk," the amateur archaeologist said.

His next trip will take him to Costa Rica.

"We're going to Tiskita, a beach on the Pacific Ocean," said Cohn, who plans to do a lot of hiking, but notes that others who take this trip tend to be bird-watchers.

Companies like Nature Expeditions and Adventure Specialists rank their trips to help clients select one that suits their abilities, needs and interests.

An "easy" ranking would probably include first-class accommodations and nature and cultural walks. Trips that include sleeping in tents or involve more strenuous hiking would be classified as "moderate." Anything more strenuous than that would probably be labeled "challenging."

Other groups that offer outdoor or eco-tourism trips include: Great Alaska Safaris, (800) 544-2261; River Odyssey's West, (800) 451-6034; American Wilderness Experience, (800) 444-0099; and Canadian Mountain Holiday Heli-Hiking, (800) 661-0252.

Elderhostels have been around for years and there's no denying their attraction. More than 270,000 people over age 55 participate each year in Elderhostel programs at 2,000 educational institutions in the United States alone.

Accommodations, meals, instruction and field trips are included in the program's tuition. A weeklong program in the continental United States averages $390 per person.

Outside of the United States, there are more than 70 countries that participate in the program. About 25,000 people take advantage of it annually. Some go for educational programs, others offer their talents through the service program. For example, you can help curate for a museum or participate in community development, sustainable agriculture or education.

Those programs run anywhere from six to 21 days and the program costs are tax-deductible. Call (617) 426-8056.

For those who want to fill their minds, not just their shopping bags, there are also opportunities to combine travel with education.

Oxford University has been holding residential summer courses since 1888. Through its continuing education department, you can choose from a number of courses or programs, some in conjunction with American universities or groups.

The Oxford-Florida State University Adult Summer Program invites participants to live as students in Christ Church and take courses such as "Renaissance Art," "The English Village" or "Box Office Bard: Shakespeare on Film."

Courses are taught by British faculty in small seminar and tutorial groups. Call Florida State University at (850) 644-7540.

The Smithsonian Institution also has a program with Oxford that combines lectures with social events and field trips. The seminars are led by specialist tutors. Seminars include "Collections and Collecting," "Shakespeare and the World of the Court," "The English Garden in History" and "The English Country House." Call the Smithsonian National Associate Travel Program at (202) 357-2700.

Another option is U.C. Berkeley's Extension program, which has trips with scholars to Oxford, as well to Paris, Florence, Sicily, Turkey, Mexico, India, the south of France and New Orleans. Call (888) 209-7344, ext. 46 .