From 1600 to the Hill and back, there's a lot happening along Pennsylvania Avenue. Here's a sampling of activities, nearly all of them free:

WHITE HOUSE TOURS -- Skip through the big guy's house for a free look Tuesdays though Saturdays, 10 to noon, except during state visits.

WESTERN PLAZA -- A two-hour "Get Out and Vote" rally begins at 11:30 Saturday, with live music.

NATIONAL THEATER -- Saturday at 9:30 and 11, there'll be two free performances for kids by Dancers of the Third Age, a modern dance troupe whose ages range from 60 to 87 years.

Don't forget that the musical "Cats" will run through November 25; there are a few partial-view single seats left at $40, with standing room for $10.

THE PAVILION -- The New Age Dancers perform Friday at 7:30 on the main stage.

On Saturday at 2, the D.C. Contemporary Dance Company presents "Beat the Street," and at 4 there'll be concert band selections from Different Drummers. George Wade and Company take to the stage at 6 with a rhythm and blues show.

On Sunday at 3, Dean Olawski plays popular tunes. While you're there, remember the Post Office Tower. It's open every day, 9 to 5, and offers a splendid view of the city.

FEDERAL BUREAU OF INVESTIGATION -- The FBI gives free tours weekdays from 9 to 4:15, providing a history of the bureau, exhibits, a peek at the crime laboratory and a firearms demonstration. Enter via the E Street door.

NATIONAL ARCHIVES -- Monday through Saturday, enter on the Pennsylvania Avenue side of the building for the "Guardian of Our History" exhibit on the second floor; it celebrates the Archives' 50th anniversary. On the fourth floor, a 12-minute slide show on genealogical research runs continuously from 9 to 5. The Pennylvania Avenue side is closed on Sundays.

On the other side, the Constitution Avenue entrance is open every day from 10 to 5:30 for viewing the Declaration of Independence and the Bill of Rights.

NATIONAL GALLERY OF ART -- It offers a host of free activities. "Painting of the Week" tours run Tuesdays through Saturdays at 1, Sundays at 2 in the East Building, upper level. Through Sunday, see Charles Demuth's "Chimneys and Water Tower" from the Alfred Stieglitz collection.

In the West Building Rotunda, two different daily tours feature art topics, Tuesdays through Saturdays at noon and 2, Sundays at 2:30 and 6. This week: "Art As Propaganda" and "The Index of American Design."

The museum offers a film series on art in the East Building Auditorium, Wednesdays through Fridays at 12:30, Sundays at 1. Through Sunday, see "The American Vision" and "American Light: The Luminist Movement, 1850-1875."

Past Hollywood hits are shown Saturdays at 2, Sundays at 6. Showing this weekend: "Valley Town" and "The Grapes of Wrath."

Tuesday through Friday at 2, "A Place To Be," tells the story of constructing the East Building.

The auditorium also has free lectures Sunday at 4. This Sunday: "Thomas Moran's Watercolors of Yellowstone."

And finally, every Sunday evening at 7 in the West Building's East Garden Court, there is a free live concert by the National Gallery Orchestra or a visiting group. This Sunday and next, the Portland String Quartet and the Ernest Bloch Quartet will be performing. The performances are also heard live on WGMS AM/FM (570 & 103.5).

Museum hours are 10 to 5 Monday through Saturday, noon to 9 Sunday.

CAPITOL -- 35-minute free guided tours are offered from 9 to 3:15 every day but Christmas and New Year's. The tours combine history of the Capitol, a walk through the old Supreme Court chambers, Statuary Hall and the Rotunda, and a trip into either the House or Senate chamber.