The difference between fan and fanatic is a hundred miles or so -- from here to Carlisle, Pennsylvania, the summer home of the world champion Washington Redskins.

To see the Redskins practice, Lynn Humphries has come up from Gambrills, Maryland, with her husband, Joe, and their children, Debby and Sonny. It's one of the things they'd planned for their vacation. Two years ago they did the same, having their pictures taken "with Joe and Mark Moseley," she says, and picking up lots of autographs.

Joe Theismann is her favorite, but it hasn't always been that way. When Sonny was born, well, it was 1972. "That was his last year," she says, referring to Jurgensen. Funny thing, they almost named the kid Joe, after his father. Now she kind of wishes they had, after the current quarterback.

Lynn Humphries says she's in Carlisle to see the Skins for one simple reason: "We can never get tickets."

But it might be a little easier this Saturday when the Skins scrimmage the Baltimore Colts at the Carlisle High School football field at 1:30. Admission is $3 and tickets go on sale at the gate at 11:30.

And there are those two-a-day practices that are open to the public, until Wednesday, at the Dickinson College practice field on West High Street.

Fans show up early for the practices to greet the players as they arrive. "Hey, how you?" asks the fan. "I'm still here," answers the player. The Skins have until August 29 to cut their roster down to 45 from over a hundred, including draft choices; the winnowing is one of the goals of training camp.

The other goal obviously is to get the team in shape. The practices stop being public after Wednesday because by then, according to public-relations man John Konoza, "You start to develop your offensive character." Training camp ends August 17.

The fans on the edge of the practice field keep a respectful distance -- with cameras, pens and 4i-x-5i colored papers at the ready. Two teenage girls sit at a folding table and sell Skins T-shirts, caps and 1983 Fan Guides.

Minnesota! Minnesota!, Joe Gibbs calls to the offense, wearing white jerseys.

Black! 50! Black! 50! cries the quarterback.

Yellow 31! Yellow 31! It's just another play.

Across the field and dressed in red, dancing along a yardline like members of a chorus line, the defense runs agility drills. The calls they yell sound musical.

All the little things about the players that a fan can store away for the cold winter in front of the TV. How, when leaving the field after practice, the receivers don't just grab cans of Gatorade from the cooler: They throw them to each other. How, when leaving the field, Theismann doesn't leave the field, but jogs around it once for good measure -- then lifts weights.

Practices are from 9 to 11 and 4 to 6 weekdays. There's no practice Wednesday afternoons because that night at 7:30 the team scrimmages itself under the lights at the high school a few blocks west.

Around 7, as the suited-up team rides to the field in schoolbuses, kids stop along the sidewalk and signal thumbs up as they pass. How are they different from high school players? Just bigger. Better. Cockier. Richer.

The locals ride in on bicycles to watch, or jog to the field to see the big guys up close and in person. Theismann and Tom Owen sit on their helmets at the 50 watching the action near the end zone. About 75 people dot the stands. No one keeps score.

"You can see when it's a running play; they get down harder," says one boy in a group of youngsters encircling a man who is taking notes.

The boys leave. A closer look at the cover of the notebook reveals that the man is writing Xs and Os in a scouting book.

Is he with the Skins? Scouting the rookies to decide who makes the team?

Screwing up his face, he says quietly, "I'm a scout for the Eagles."

Ah yes, there's a season after summer.

D The center of Redskin action isn't always the football field. Within an hour of practice you'll see the big men walking on West High Street to the field, or returning to the Dickinson dormitories afterward.

For not being executives, they spend an awful lot of time in meetings. But after the afternoon practice, some head west on High Street and around the corner to the Fireside Restaurant for liquid refreshment before returning to the training table for dinner. Then more meetings at the college. From 10 to the 11 o'clock curfew, they're free. During that time they might show up in the town square at the Gingerbread Man, and maybe play some Jungle Lord or Super Pac-Man -- possibly eat gingerbread with whipped cream. With a rococo interior that suits the name, the Gingerbread Man looks like an ice-cream parlor from the outside. On the menu are mostly drinks, sandwiches and subs, but you feel right at home; it puts you in mind of Clyde's.

Evenings, George Allen used to send an assistant to Massey's Burger and Shake to take out a vanilla one. Coaches come and go, but shakes -- they still sell 'em at Massey's, a few hundred yards west of the practice field.

Someone may call ahead to Rillo's to let the Italian restaurant know the Skins plan a visit that evening. "Just hang around the bar and they'll be here around 10," advised a waitress. At 50 Pine Street, Rillo's makes its own fettucine and ravioli. Ask for the sausage-and-peppers appetizer "Redskins style," and they'll cover it with tomato sauce, onions and mozzarella cheese. The smell of the garlic, the roar of the cappuccino machine.

D When asked what there is to do in Carlisle, one wag in the Redskin camp replied, "Leave."

Carlisle has one movie theater.

But if you're on the outside looking in, the Pennsylvania heartland possesses considerable charm: chicken corn soup festivals, stone barns, steepled churches, cornfields, cows in clusterssand sheep unshorn.

At the intersection of Hanover and High streets, the town square -- where the public whipping post used to stand -- consists of two churches and two courthouses. George Washington attended the Presbyterian church, dating from 1757. The county courthouse's sandstone pillars bear the scars of a shelling by Confederate soldiers who were heading for Gettysburg on July 1, 1863.

Also of note is Carlisle Barracks, the oldest (1757) Army post in the country, home of the Army War College, where top officers are trained. The Hessian Powder Magazine Museum, built in 1777, is open weekends and holidays from 1 to 4 until September 30. Exhibits outline the history of the barracks and tell about the Indian School once there -- made famous by Olympian Jim Thorpe and his football team. Upton Hall houses a display of memorabilia from the life of General Omar Bradley. It's on U.S. 11 (North Hanover Street extended).

Catherine Casey, who runs the Carlisle office of the Cumberland County Tourist Council, advises, "When driving through the barracks, be very careful. Don't go over 15 miles per hour, because it's a federal ticket. I almost got one once. And you must stop if you see someone crossing a crosswalk."

Other than the barracks, she says, in Carlisle there's "not very much -- other than historical buildings. I shouldn't say that."

What does she do for fun? "I usually go to Harrisburg and play cards," she says, adding, "just for pennies, of course."

You want rustic, you got rustic: a mill, two covered bridges and an eight-sided schoolhouse within easy driving distance. With the Blue Mountains to your north, scenic Route 641 west leads to Laughlin's Mill in Newville, 11 miles from Carlisle. The grist mill was built in the 1760s. Go three more miles to Thompson's bridge, on Bridgewater Road on the right. The covered bridge is closed to traffic; underneath it runs the winding Condoguinet Creek, noted for its bass fishing. (For trout fishing, try the Yellow Britches Creek south of Carlisle.) Another four miles, turn left on Covered Bridge Road, which leads to Ramp's Bridge. (Watch for a homely little dog with matted hair.) Return to Route 641; another two miles west takes you to Newburg, where, turning right on Exchange Street, you can see an old octagonal schoolhouse.

Back in Carlisle, Dickinson College, which has more than 1,700 students, is historic for more than its Redskins summer football camp.

The fateful summer of 1863, the college campus was occupied first by Confederate troops. After Gettysburg, the college buildings were used as hospitals for wounded Union soldiers and captured and wounded Confederates.

The architect of the U.S. Capitol, Benjamin Latrobe, designed the oldest building, called Old West, fashioned from native blue limestone in 1804.

Plaques pay tribute to personages of varying celebrity. According to the plaque at West Street and High, George Washington reviewed the troops there on October 11, 1794, before they marched to western Pennsylvania to suppress the Whiskey Rebellion.

Nearby on campus, over a stone bench, a plaque tells yet another tale: "Rest here a while, Dickinsonians," it says, "near the east college gate where for more than 40 years Noah Pinkney, former slave and Christian gentleman, sold pretzels and gave lavishly of his friendship . . . He passed over Jordan at the age of 77 on August 6, 1923, and the trumpets sounded on the other side."

More recently, homage is freely paid to other men. Everywhere in Carlisle, storefronts herald the Skins with welcome signs, such as "Welcome Redskins Pool Chemicals." Lovingly draped over a display of clocks in a jewelry store is T-shirt 44; a football rests among the baubles.

Says Casey at the Tourist Council, "There's quite an interest in the Redskins, especially for the high-school age.

"They have to train somewhere, I know," she says. "But it never made any sense to me -- they train here, yet they call them the Washington Redskins. I think they should be the Carlisle Indians." HOW TO GET THERE From Washington, take I-270 north to Frederick, where you pick up U.S. 15. Continue north to Gettysburg. From here, many roads lead to Carlisle, but for a scenic one, take Route 34 north. It becomes Hanover Street in town. Turn left on High Street (at the town square), pass through the college campus, and the Redskins' practice field will be on the left. To get to Carlisle High School for the scrimmage Saturday at 1:30, continue west a few blocks on High Street to the underpass. Go beneath it and keep right at the fork (Orange Street). The high school is at the end of Orange Street. FOR MORE ON CARLISLE Here's where to stop for more information, such as brochures on Carlisle Barracks and Dickinson College and maps of Cumberland County. CUMBERLAND COUNTY CHAMBER OF COMMERCE, 212 North Hanover Street. Monday through Friday 9 to 5. 717/CH3-4515. CUMBERLAND COUNTY TOURIST COUNCIL, in the Colonial Peddlers shopping mall off North Hanover Street (U.S. 11), north of Carlisle. Monday through Saturday 10 to 5, Sunday 1 to 5. 717/243-9350.