Arlington National Cemetery
Memorial Drive, Arlington. 8 a.m.-5 p.m. Admission free. 703/607-8052.
Changing of the guard at the Tomb of the Unknowns. Starting every half-hour 8 a.m.-5 p.m.
Bureau of Engraving and Printing
14th and C streets SW. Visitors center: 8:30 a.m.-3:30 p.m. Tours: 10 a.m.-2 p.m. Monday-Friday. Metro: Smithsonian. 202/874-2330.
U.S. paper-currency tours every 15 minutes 9 a.m.-2 p.m. Monday-Friday. Valid photo ID required. Bags not allowed on the tour. 866/874-2330.
Clara Barton National Historic Site
5801 Oxford Road, Glen Echo. Admission free. 10 a.m.-4 p.m. daily. Tours on the hour, starting at 10 a.m. 301/492-6245.
The 1997 discovery of Clara Barton’s 1861-1868 Office to Locate Missing Soldiers.
Department of the Treasury
15th Street and Pennsylvania Avenue NW. 202/622-0896.
Tours suspended until further notice.
10th and E streets NW. 202/324-3447.
Tours suspended until further notice.
Hillwood Museum and Gardens
4155 Linnean Ave. NW. Reservations required. 202/686-5807.
South bank of the Tidal Basin. 202/426-6841. Open 8 a.m.-midnight. Metro: Smithsonian.
Museum exhibits 9 a.m.-5 p.m. daily.
F Street and New Hampshire Avenue NW. 202/416-8340.
Tours 10 a.m.-5 p.m. Monday-Friday; 10 a.m.-1 p.m. Saturday, Sunday. Free.
Constitution Avenue and 23rd Street NW. 8 a.m.-midnight daily. Metro: Foggy Bottom. 202/426-6841.
Museum exhibits 9 a.m.-5 p.m. daily.
James Madison’s home and burial place on Route 20, four miles south of Orange, Va. 9:30 a.m.-5 p.m. daily for tours. Admission $3.50-$7.50. 540/672-2728.
George and Martha Washington’s home and burial place at the south end of the George Washington Memorial Parkway. 9 a.m.-5 p.m. daily through Oct. $5-$11. 703/780-2000.
Pennsylvania Avenue between Seventh and Ninth streets NW. 10 a.m.-5:30 p.m. daily except holidays. Metro: Archives-Navy Memorial. 202/501-5000.
Museum housing the Declaration of Independence, the Bill of Rights and the U.S. Constitution.
National Shrine of the Immaculate Conception
Michigan Avenue and Fourth Street NE. 202/526-8300.
Guided tours. Monday-Saturday 9-11 a.m. and 1-3 p.m. Sunday 1:30-4 p.m.
National World War II Memorial
17th Street between Constitution and Independence avenues. 9:30 a.m.-8 p.m. daily. 800/639-4WW2.
9000 Richmond Highway, south of Alexandria. 10 a.m.-5 p.m. daily. 703/780-4000, Ext. 27.
Limited group tours available. Public tours suspended until further notice. 703/695-3325.
Franklin D. Roosevelt Memorial
West Basin Drive. Metro: Smithsonian. Open 24 hours daily. Interpretive ranger staff on hand to answer questions 8 a.m.-11:45 p.m. 202/426-6841.
Site explores the legacy of the 32nd U.S. president, 9 a.m.-5 p.m.
Old Town Trolley’s two-hour day tours make 18 stops, including the White House, the Capitol and Arlington National Cemetery. Tours begin 9 a.m. daily. $24 adults, $12 children. Evening tours also available. 202/832-9800.
First Street and Constitution Avenue NW. 9 a.m.-4:30 p.m. Monday-Saturday. 202/225-6827.
Tours available 9:30 a.m.-3:30 p.m. Free timed tickets can be obtained at 8:15 a.m. on the day of tour at the West Front of the Capitol.
Exterior walking tours by the U.S. Capitol Historical Society. 10 a.m. Monday. Meet at the Massachusetts Avenue exit of the Union Station Metro stop. $10. 202/543-8919, Ext. 17.
U.S. Supreme Court
1 First St. NE. Open 9 a.m.-4:30 p.m. Monday-Friday. 202/479-3030.
Public lectures in the courtroom every half-hour 9:30 a.m.-3:30 p.m. when the court is not hearing arguments. Public seating for arguments when the court is in session is on a first-come, first-served basis on the day the court meets. Call ahead to confirm court meeting location.
Vietnam and Korean War veterans memorials
Bacon Drive and Constitution Avenue NW, and French Drive SW. 8 a.m.-midnight. Metro: Foggy Bottom. 202/426-6841.
16th Street and Constitution Avenue NW. 202/619-PARK. 9 a.m.- 4:45 p.m. Timed tickets are available each day on a first-come, first-served basis at the 15th Street NW kiosk. 800/967-2283.
Washington National Cathedral
Massachusetts and Wisconsin avenues NW. 202/537-6200. 10 a.m.-5 p.m. daily; 10 a.m.-4:30 p.m. Saturday. Docent-guided tours 10 a.m.-3:15 p.m. Monday-Saturday; 12:30 p.m.-2:45 p.m. Sunday. No tours on holidays. $3 adults, $1 children.
Tea tours 1:30 p.m. Tuesday, Wednesday. Call for reservations and fee. 202/537-8993.
The White House
1600 Pennsylvania Ave. NW. 202/456-7041 or 202/456-2322.
Public tours are available Tuesday through Saturday if they are arranged with a congressional office and if the group has at least 10 persons.
White House Visitor Center
1450 Pennsylvania Ave. NW. 202/208-1631.
Open 7:30 a.m.-4 p.m. daily.
Weekly walks in Foggy Bottom, Georgetown, Lafayette Square, other neighborhoods. Call for schedule. Most tours $5-$10. 202/484-1565 or www.washingtonwalks.com.
al-Event:Anecdotal History Walk
Author-historian Anthony Pitch leads a two-hour anecdotal history walk on “Georgetown Homes of the Famous and Infamous.” May 1. Meet at 11 a.m. at the R St. steps leading up to Georgetown library, near corner Wisconsin Ave. $15 each, weather permitting. Reservations not necessary. E-mail firstname.lastname@example.org or 301/294-9514.
1426 N. Quincy St., Arlington. Showtimes 7:30 p.m. Friday and Saturday; 1:30 and 3 p.m. Sunday unless otherwise noted. $1.50-$2.50. 703/228-6070.
The Audubon Naturalist Society holds free weekend walking tours. 301/652-9188.
Druid Hill Park, one mile off Interstate 83 (Exit 7), Baltimore. 410/366-LION. 10 a.m.-4 p.m. daily. $11 adults, $9 seniors, $7 children 2-11, free for children younger than 2.
Green Spring Gardens Park
4603 Green Spring Road, west of Alexandria. 703/642-5173.
Horticulture Center. 9 a.m.-4:30 p.m. Monday-Saturday; noon-4:30 p.m. Sunday.
Department of Commerce, 14th Street and Constitution Avenue NW. 9 a.m.-5 p.m. daily. Last admission 4:30 p.m. $2-$5. Discounts for children, seniors. 202/482-2825.
Shark feedings 2 p.m. Monday, Wednesday and Saturday.
Piranha feedings 2 p.m. Tuesday, Thursday and Sunday.
National Aquarium in Baltimore
501 E. Pratt St., Pier 3 at the Inner Harbor, Baltimore. 9 a.m.-8 p.m. Sunday-Thursday; 9 a.m.-10 p.m. Friday, Saturday. $9.50-$17.50. 410/576-3800 or 410/727-FISH.
?Coastal Connections: Dolphins at Our Shores.? High-tech graphics and natural behaviors demonstrate the mammals’ abilities. Call for times.
U.S. National Arboretum
3501 New York Ave. NE. Grounds open 8 a.m.-4:30 p.m. daily. 202/245-5898.
?The Making of a Garden.? Lecture with Tom Wirth. 2-3:30 p.m. May 21. $4-$5.
?Conservation Portraits: Botanical Illustrations of Japan’s Endangered Plants.? 8 a.m.-4:30 p.m. Through June 30.
National Zoological Park
3001 Connecticut Ave. NW. Grounds open 6 a.m.-8 p.m.; buildings open 10 a.m.-6 p.m. daily. 202/673-4800.
?The Gathering.? Chimpanzee sculptures by Bart Walter. On permanent display.
Panda exhibit of Mei Xiang and Tian Tian. Open to the public 9 a.m.-4:30 p.m. daily.
Sea lion training and elephant care session. 11:30 a.m. most days.
The Amazonia Science Gallery depicts a living river system, a rain forest and field-research exhibits. A biological-diversity study center has a scanning electron microscope and a collection of live insects and amphibians.
Tudor Place Historic House and Garden
1644 31st St. NW. 202/337-5815.
House and garden tours available Sunday afternoons and all day Tuesday-Saturday. $3-$6.
U.S. Botanic Gardens
100 Maryland Ave. SW. Open 10 a.m.-5 p.m. daily. 202/225-8333.
?How Plants Work ? A Guide to Being Green.? Permanent exhibit.
Pickup basketball. 7:30 p.m.-10 p.m. Monday-Thursday, 7:30 p.m.-midnight Friday and Saturday, 9 a.m.-12:45 p.m. Sunday. $2-$3. Ferlazzo Building, 15941 Donald Curtis Drive, Woodbridge, Va. 703/792-4242.
College Park Bicycles
Bicycle repair classes, training races, roller races. 301/864-2211.
Mid-Atlantic Off-Road Enthusiasts
Mountain-bike rides around the region for all levels. 703/502-0359 or www.more-mtb.org.
Area rides for all levels. 202/363-TOUR for schedule. www.bikepptc.org.
Men’s Flag Football League
The IFFLMen’s Spring Flag Football League is seeking players for its season that began March 20. For team registration and league information go to WWW.IFFL.US or call the IFFL league line at 703/257-2400.
Virginia Academy of Fencing
Classes for children 8 and older. 5410 Port Royal Road, Springfield. 703/321-4922.
C&O Canal walks
C&O Canal National Historical Park, 11710 MacArthur Blvd., Potomac. Guided walks may be available on weekends. $4 per car or $2 per walker or biker. 301/299-3613.
The C&O Canal Association. Walks, canoe trips, bike trips and opportunities to restore the canal towpath. 301/983-0825.
Capital Hiking Club
Year-round Sunday hikes using chartered bus with pickup points in the District, Virginia and Maryland. Monthly moonlight hikes on the C&O Canal from early spring to late fall. www.capitalhikingclub.org
Center Hiking Club
Weekend and Wednesday evening hikes. 703/527-2349.
Freestate Happy Wanderers
Walks every day on six trails through Maryland. 410/437-2164 or 301/490-5850 before 9 p.m. to request a brochure.
Mountain Club of Maryland
Day and overnight backpacking hikes; bike and canoe trips; cabin, car and tent camping. Beginners and experienced hikers welcome. Call for schedule. 410/377-6266.
Northern Virginia Hiking Club
Weekly hikes. www.nvhc.com or 703/440-1805.
Wanderbirds Hiking Club
Chartered buses depart from 17th and K streets Northwest at 8 a.m. every Sunday, with pickups at selected suburban stops. Bring lunch and water. Beginners and experienced hikers. $14. Reservations required. See www.wanderbirds.org for schedule. 301/460-3064.
Broad Run Riding School
Riding lessons for children and adults and summer day camps for children 6-16. Midland, Va. 540/439-9586.
Brundage Equestrian Enterprises
Guided trail rides by appointment. 966 Millwood Road, Great Falls. $46 for two hours. 703/759-2474.
Equilibrium Horse Center
Indoor and outdoor arenas, lessons, trails and cross-country courses. 1685 Underwood Road, Crofton, Md. 410/721-0885 or 410/573-0545.
Fairfax County parks
The Fairfax County Park Authority Equestrian Center features practice jumping in the indoor and outdoor rings and on the cross-country trail. $3.50-$6. Frying Pan Park, 2709 W. Ox Road, Herndon. 703/437-9101.
Fort Valley Stables
One- to two-hour guided horseback tours or half-day or full-day horseback riding in the Massanutten Mountains. 540/933-6633 or 888/754-5771.
Gone Away Farm
Guided trail rides for any level. Saturday by appointment and 11 a.m. Sunday. Potomac Polo Club, 18410 Beallsville Road, Poolesville. $40 per person for two hours. 301/972-7757.
Unguided trail rides by appointment. Racefield Road, Aldie, Va. $30 for one hour. 703/327-6117.
The Marriott Ranch
Guided trail rides. 10 a.m., 2 p.m. and 4 p.m. weekends and holidays; 10 a.m., noon and 2 p.m. Tuesday-Friday. 5305 Marriott Lane, Hume, Va. $28.50 weekends and holidays, $26.50 otherwise. 540/364-3741 or 540/364-2627.
Merry Mount Equestrian Center
Group lessons Monday-Thursday, Saturday; private lessons available Monday-Saturday. 8801 Frank Tippett Road, Upper Marlboro. Prices vary. 301/868-2109 or www.merrymountequestrian.com.
Boarding stables and lessons. 15607 Croom Airport Road, Upper Marlboro. 301/627-3631.
Wheaton Regional Park Stables
Beginner and advanced riding classes for children and adults. Escorted trail rides Sunday afternoons. $25 per person for one hour. 1101 Glenallen Ave., Wheaton. 301/622-2424.
Sportrock Climbing Center
Equipment and indoor and outdoor rock-climbing instruction for individuals and groups. 14708 Southlawn Lane, Rockville. 301/762-5111.
Rockville’s recreation department offers daily indoor and outdoor rock climbing, along with classes. 301/217-6890.
West Potomac Rugby Club
West Potomac Rugby Club, a social and competitive Division III club, is looking for recruits of all ages. For more information on practices and team events, see www.dcrugby.org or call 202/236-3548.
D.C. Road Runners
Weekly runs throughout the area. 703/241-0395, Ext. 3.
Montgomery County Road Runners
Weekly training runs and semimonthly races. 301/353-0200.
Road Runners of America
The club updates its race hot line every week. 703/683-RRCA.
Senior Softball League
Northern Virginia Senior Softball (average age 65) seeks men 50+ and women 40+ for softball games on Fairfax County fields Tuesday and Thursday mornings, April 12 to Aug. 12. 2005 fee of $70 for Fairfax County residents, $110 for nonresidents. For more information, call Dave 703/524-5576, or Joyce, 703/860-1876.
Local chapters. Call for schedule. 703/354-1735 or 410/730-3514.