It's sharp now up in Lancaster and Berks Counties in southI eastern Pennsylvania. The pumpkins that made the fields as orange as a flower patch have all been stored away and summer's cornfields are now just brown geometric patterns. The mists lie low in the foothills of the Kittatinny Mountains, and up on the ridges the golden eagles ride the air currents of the sharp north winds, thinking about moving south.

November is the month to see this handsome country, to spend a weekend close to nature and to warm yourself later before the fires of a country inn. Try the new Cameron Estate Inn in Mt. Joy and make a side excursion to Hawk Mountain Sanctuary, where the view is laid out for your inspection for 70 miles.

Cameron Estate is the new venture of Betty and Abe Groff, the Pennsylvania farm couple whose Groff's Farm Restaurant drew plaudits from James Beard and Craig Claiborne. Only a few weeks ago the Groffs opened their new inn, once the home of Lincoln's controversial Secretary of War Simon Cameron, the man who is said to have defined an honest politician as "one who when he is bought will stay bought."

Mt. Joy is not exactly on the beaten track, but this is one of the reasons for seeking it out. This is deep country where the night outside your window is silent and dark and the farm smells mingle with the autumn wind when you walk out the door. Staying at Cameron Estate is like being a member of a country houseparty. Twenty-five guests pack the house, a baronial mansion now designated by the Department of the Interior as a National Historic Landmark.

The house has wide halls and open staircases that make you suddenly realize how cramped we live in the 20th century. The floors are beautiful with age, polished to a burnished patina, and it is just too bad that the inn has been furnished with Victorian reproductions and (except in the front hall) American imitations of Oriental rugs. But the bedspread on our bed in Mr. Cameron's room was a beautiful patchwork quilt, and the dining room is cheerful with candles and cabbage-rose wallpaper and a huge fireplace.

Arriving on the very first night that the inn had served food, we found the dinner (prepared by the 22-year-old graduate chef of the Hotel Hershey four-year culinary apprenticeship) good by the most demanding standards. Though the Groffs made their reputation with Pennsylvania Dutch food, this is lighter and more sophisticated fare. The liquor license is pending.

Upstairs in Cameron's bedroom ($70 plus tax), we could have held a small square dance, and the bathroom was scarcely less commodious. All plumbing is the last word in modern convenience, however one can't help thinking that clawfoot tubs and old-fashioned faucets would have gone better with the ambiance. The other rooms start at $45, but since they were all occupied I did not see them.

A continental breakfast at Cameron Estate is served at 8 a.m. in the dining room. Unfortunately, it's a bit difficult to get an earlier start. We were up with the dawn since we were planning to go to Hawk Mountain but, to avoid starting out breakfast-less, we had to wait until the usual hour to fill our thermos with coffee and get a hot package of Danish for the road. If you want to make the most of your day in this country, it might be well to mention early plans the night before. Cameron Estate Inn's phone number is 717--653-1773.

Hawk Mountain is the wilderness mountain sanctuary near Hamburg, purchased in 1934 and preserved from the inroads of civilization by Rosalie Edge. It is now maintained by a private group, and everything about it is awesome -- from the massive boulder piles in the lookouts over the valley below to the untouched woods through which the trail winds.

Serious climbers come to Hawk Mountain with their binoculars and telephoto lenses, backpacks and bird guides, and the three-quarter-mile climb to the top is well billed as rugged. After all, this mountain rises 1,521 feet. Though you come most of this way by car, enough is left to make it quite a journey. But even desultory hikers can trek as far up as the south lookout where a view to make you catch your breath is spread out below you. Don't leave home withoutbinoculars.

The sanctuary nature center is well managed, with stuffed hawks of every sort overhead on wires to acquaint you with what you might see. Outside the window a huge tree is decorated with every imaginable feeding station for birds, and below on the ground the chipmunks feed. On the walls inside you can follow the story of the purchase of Hawk Mountain and there's a wonderful old photo of Rosalie Edge, wearing a proper hat, hiking boots and a stern expression. On the way out, the bulletin board sports a drawing of James Watt, "quite possibly" (says the caption) "the most inappropriate Secretary of the Interior in the history of the country." This sanctuary gets no funds from the federal system.

There aren't very many golden eagles left in America, but chances are good you'll see some at Hawk Mountain in November.

If you think ahead, you can lunch on the way home at the Groffs' other establishment, Groff's Farm Restaurant back in Mt. Joy. This has become increasingly famous, especially since Betty wrote a cookbook with its recipes and People magazine carried an interview with her. You can't get in with a shoehorn unless you call days ahead, and it would be a shame to be in the neighborhood and miss it because it's a show. Call 717-653-2048.

Both Groffs come from large farm families, so this is simple, hearty Pennsylvania Dutch cooking at its best, served up with style. "This is one of the steadfast outposts of true Americana," murmured James Beard in print, and the rush was on.

The Groffs like to pretend their guests are all just friends, so there's no menu. The waitress offers fruit cup or a wonderful ham and bean soup as a first course for lunch, but everybody gets chicken Stoltzfus -- chicken in cream sauce with crispy bits of pastry throughout. The bread is homemade and so are the pickled relishes, and the black raspberry crumb pie had the lightest crust I ever tasted. I wasn't there for dinner, but they say it starts with small pieces of chocolate cake and cracker pudding because Betty Groff wants her guests to enjoy them before they get stuffed. It's all served in a nice old 1756 stone farmhouse overlooking a springfed pond which is home to a pair of swans named Anthony and Cleopatra, big and sure enough of themselves to be more than a match for the resident Irish setter, Brandy.

It's good food and reasonable ($6 per person at lunch) but for me the show's the thing. Betty Groff may well be the least-inhibited extrovert in the restaurant business. When she sashays into the dining room to lead the singing of Happy Birthday with her cornet, she holds them all in the palm of her hand. There has to be a birthday; she simply selects one or two closest to the current date, and when she finishes up, Abe comes in to bestow kisses on the birthday ladies while she does the same for the gentlemen. After this come wedding anniversary tributes, for which she renders "I Want a Girl Just Like the Girl . . . " and I swear I saw a customer wipe away a tear when it was all over.

Putting away the cornet, Betty chats up each table in turn and there isn't a last name in the house. Everybody at Groff's is just plain folks. From the ultra-suede crowd to the bus-tour customers, they eat it up.

Lancaster County has had difficulty preserving its picturesque beauty in the face of pressure to build tourist attractions, but the area around Mt. Joy has not suffered.

So rural is this part of the world that the roads themselves, narrow and unmarked, become an adventure. Groff's Farm Restaurant address is ''fourth farm on the left on Pinkerton Road.'' You locate Cameron Estate Inn by spotting an ancient Presbyterian Church and turn right by the graveyard. Pretty Rte. 501 north to Berks County is innocent of billboards and a pleasure from start to finish. This unspoiled countryside reflects the deeply religious, hardworking people who settled it, and sometimes their philosophy comes as a shock to city people.

At one turn in the road we came unexpectedly upon a rare billboard quoting from the book of Matthew, chapter and verse of which escapes me.

"Are you sure you are on the right road?" it asked in large letters.

In our car, until it was understood that I was quoting from a billboard, this caused some misunderstanding.