GETTING THERE: There are no direct flights to Quebec from Washington -- or from almost anywhere in the United States, for that matter. Furthermore, since Air Canada doesn't serve Washington, any trip will involve at least two airlines. For instance, you can fly U.S. Air from National to Toronto, and then switch to Air Canada ($484 round trip, but about $135 less if you stay over a Saturday). Or you can fly Delta from National to Montreal, switching to either Nordair or Quebecair ($420 round trip, but also significantly less if you stay over a weekend). Alternatively, you can fly to Montreal and then take the train for the final leg. This three-hour trip, which runs three times a day, is considered quite scenic. If you return within five days, the train costs $43 Canadian round trip ($30 American). CHA~TEAU FRONTENAC:Rooms for the period from Dec. 24 to Jan. 3 tend to fill up quickly at the Frontenac. The management says most of the space is gone by Oct. 15 -- although we called several weeks later last year, and still were able to get a room. The Dec. 25 dinner in Le Champlain tends to be booked even faster. Often, the hotel says, the tables are filled by Oct. 1. A cheaper Dec. 25 dinner-dance in the ballroom holds space longer -- usually until Dec. 1.

Current prices at the Frontenac range, in Canadian dollars, from $83 to $135 for a single room and $103 to $153 for a double. (Prices in American dollars are about 25 percent less.) A special package deal called Three Enchanted Evenings will allow you to book a room for three nights for a total of $149 U.S. These rooms can be booked only for the period from Nov. 1 to April 30. For more information and reservations, call (418) 692-3861, or write Reservations, Le Cha~teau Frontenac, 1 Rue des Carrie`res, Quebec City, Quebec Province, Canada. G1R 4P5. INFORMATION: For more information about the city, contact the Quebec Government Office of Tourism, 1300 19th St. NW, Suite 220, Washington, D.C. 20036, (202) 659-8991.