What's Doing

NSO DECORATORS' SHOW HOUSE -- Friday 10 to 3, Saturday-Sunday from noon to 5, and Monday-Thursday from 10 to 3, through Oct. 31. Tour a 10,000-square foot Neoclassical home redecorated by dozens of designers in this 33rd annual benefit for the National Symphony Orchestra. $15 in advance, $20 at the door. At 8295 Alvord St., McLean; free parking with shuttles at satellite lots. 202-416-8149.

U.S. POWERBOAT SHOW -- Friday and Saturday 10 to 7, Sunday 10 to 6. Exhibits of hundreds of powerboats in water and on land, and displays by vendors of nautical goods and services. $16, ages 12 and younger $8. At City Dock, Annapolis. 410-268-8828 or 410-267-6711.

BENEFIT BRIDAL GOWN SALE -- Friday 10 to 8, Saturday 10 to 6, shop among hundreds of donated gowns. Proceeds benefit Making Memories Breast Cancer Foundation. Doubletree Hotel Crystal City, 300 Army Navy Dr., Arlington. 703-597-2775 or 703-323-9208.

SOLAR VILLAGE -- Friday 11 to 4, Saturday-Sunday 9 to 6. Tour solar houses designed by students competing in the Department of Energy Solar Decathlon. On the Mall between 7th and 14th streets. 800-342-5363.

SHENANDOAH VALLEY HOT AIR Balloon and Wine Festival, Friday 4:30 to 7, Saturday-Sunday 7:30 to 4. Wine-tastings, balloon rides, entertainment, crafts fair, antique cars. Hot air balloon launches at 7:30 a.m. and 4:30 p.m., weather permitting. $10 per person or $30 per carload. Historic Long Branch, Route 624, Millwood, Va. 888-558-5567.

YARD SALE -- Saturday 7 to 3. Sponsored by the Alexandria Jaycees at the Anthony Lane School parking lot, 7137 Beulah St., Alexandria. 703-866-7171.

FLEA MARKET -- Saturday 8 to 2. Oxon Hill United Methodist Church, 6400 Livingston Rd., Oxon Hill. 301-839-4748.

CRAFTS FAIR -- Saturday 10 to 2, by 15 Girl Scout troops. Elks Lodge, 8421 Arlington Blvd., Fairfax. 703-818-8414.

USED BOOK SALE -- Saturday 1o to 3. Lone Oak Center, 1010 Grandin Ave., Rockville. 301-340-7458.

FALL FAIR -- Saturday 10 to 3. Entertainment, games, crafts, food vendors, Inova flu shot clinic. Andrew Chapel United Methodist Church, 1301 Trap Rd., Vienna. 703-759-3509.

FARM HARVEST DAY -- Saturday 10 to 3. Farm animals, games and crafts, antique equipment demonstrations, pumpkin- painting. $3. Ellmore Farm Center, Frying Pan Park, 2739 West Ox Rd., Herndon. 703-437-9101.

LOUDOUN COUNTRY FARM TOUR -- Saturday and Sunday 10 to 4, , a self-guided tour of Loudoun County farms. Pick up map and brochure and county libraries or Loudoun Convention & Visitors Association, 222 Catoctin Circle SE, Leesburg. 866-771-7697 or www.loudounfarms.org.

AAFSW BOOK FAIR -- Saturday-Sunday and Oct. 22-23 from 10 to 4. Used books, art objects, stamps, coin. Sponsored by the Associates of the American Foreign Service Worldwide at the State Department, 23rd and C streets NW. 202-223-5796.

QUILT SHOW -- Saturday 10 to 6, Sunday 10 to 4, by Nimble Fingers Quilters. About 250 quilts. Home Arts Building, Montgomery County Fairgrounds, Route 355 and Perry Parkway, Gaithersburg. 301-983-2179.

RENOVATORS' HOUSE TOUR -- Saturday 10 to 5, self-guided walking tour of 10 renovated Capitol Hill homes. $25, to benefit the Capitol Hill Cluster School. Buy tickets outside Eastern Market, Seventh and North Carolina SE. 202-544-0382.

"GRAND MILITIA MUSTER" -- Saturday 10 to 5. Drills, demonstrations and living history portrayals by 17th-century military reenactors. $7.50, students and seniors $6, ages 6 to 12 $3.50, younger free. Historic St. Mary's City, Route 5, St. Mary's County, Md. 240-895-4990.

AUTUMN FESTIVAL -- Saturday and Sunday 10 to 5. Entertainment, crafts, wine-tastings, food vendors. Mount Airy Mansion, 8714 Rosaryville Rd., Upper Marlboro. 31-856-1954.

HUNT COUNTRY ANTIQUES FAIR -- Saturday 10 to 5 and Sunday from 10 to 4, about 150 dealers show their American and Continental furniture and accessories. $10. Morven Park International Equestrian Center, 41793 Tutt Lane, Leesburg. 703-779-2800.

TROLLEY FESTIVAL -- Saturday and Sunday 10 to 5. Entertainment, crafts, exhibits, food vendors, children's activities. Sponsored by Myersville Lions Club on Canada Hill Road in Myersville, Md., 10 miles west of Frederick. 301-371-5762.

MARYLAND RENAISSANCE FESTIVAL -- Open Saturday and Sunday from 10 to 7, through Oct. 23. A replica of a 16th-century English village, with singers, musicians, jugglers, magicians and other performers on 10 stages; displays by more than 140 artisans; jousting tournaments; and food vendors. $17, seniors $15, ages 7 to 15 $8 (younger free). On Crownsville Road off Route 450, Crownsville. 800-296-7304.

ANTIQUE AND CLASSIC CAR SHOW -- Saturday 11 to 4. Displays of more than 400 historic automobiles by members of 22 clubs. Awards ceremony at 2:45. Rockville Civic Center Park, Baltimore Road and Edmonston Drive, Rockvill. 240-314-5022.

ARTS AND CRAFTS FESTIVAL -- Saturday 11 to 5. About 35 exhibitors, entertainment, children's activities, food vendors. Patuxent River Park 4-H Center, 18405 Queen Anne Rd., Upper Marlboro. 301-249-9761.

MULTICULTURAL ARTS FESTIVAL -- Saturday noon to 6. Family entertainment, exhibits, food vendors. A.J. Ferlazzo Building, 15941 Donald Curtis Dr., Woodbridge. 703-441-2479 or 703-451-4510.

CHRYSANTHEMUM SHOW -- Saturday 1 to 5, Sunday 10 to 3, by the Potomac Chrysanthemum Society. Brookside Gardens, 1800 Glenallan Ave., Wheaton. 301-384-5731.

OKTOBERFEST -- Saturday 3 to 10, Sunday 10 to 3. Entertainment, traditional German foods, children's activities. St. Mary, Mother of God Church, 727 Fifth St. NW. 202-289-7771.

ANTIQUE CADILLAC SHOW -- Sunday 9 to 3, displays of vintage Cadillac and LaSalle automobiles. Capitol Cadillac Company, 6500 Capitol Dr., Greenbelt. 301-894-8026.

BRIDAL SHOWCASE -- Sunday noon to 4. Displays by vendors of wedding-related goods and services. Kentlands Mansion, 320 Kent Square Rd., Gaithersburg. 301-258-6425.

IRISH FESTIVAL -- Sunday noon to 6. Music and dance, food vendors. Van Dyck Park, 3730 Old Lee Hwy., Fairfax. 301-822-6582.

BENEFIT CABARET -- Monday at 6, by Shakespeare Theater Company members. Donation $35, reserved table $100, for Hurricane Katrina relief programs. Mimi's American Bistro, 2120 P St. NW. 202-547-1122.