FIELD OF SCREAMS -- 6:30-9:30 p.m. today, tomorrow, Saturday and Sunday. Thirty-minute "haunted" forest walk and play area with haystack, pumpkin painting and moon bounce. Olney Boys and Girls Community Park at Freeman Fields, 4501 Olney-Laytonsville Rd., Olney. $10 for the trail; $5 for the children's play area. 301-570-7049 or www.obgc.com.

HALLOWEEN CONCERT -- 7:30 p.m. tomorrow. The Arts at Westmoreland will hold its annual Halloween concert, featuring musicians performing in costume, games and refreshments. Westmoreland Congregational United Church of Christ, 1 Westmoreland Circle, Bethesda. Free. 301-229-7768.

MONTGOMERY COUNTY GHOSTS -- 7 p.m. tomorrow and Saturday. Walking tour of the Beall-Dawson House and the Old Baptist Cemetery in Rockville. Inside the historic house will be a storyteller who will share a county ghost story. Tour starts at Route 28 and West Montgomery Avenue, Rockville. Reservations recommended. $12. 301-340-2825.

PET AND PERSON HALLOWEEN -- 3 p.m. Saturday. Booktopia and MacArthur Pet Shop in Bethesda will host a Halloween Pet and Person Costume Party, including a parade, food, pet treats and prizes. 4611 Sangamore Rd., Bethesda. Free. 301-320-3998.

HALLOWEEN BASH -- 8:30 p.m. Saturday to 12:30 a.m. Sunday. The Catholic Alumni Club will hold a Halloween mixer at the Knights of Columbus, 9707 Rosensteel Ave., Silver Spring. $10, members; $15, nonmembers. 301-530-6288 or www.dcsinglecatholicpro.org.

FALL FROLIC -- 10 a.m.-5 p.m. Saturday. Crafts, live music, dancing and Halloween activities. 7300 MacArthur Blvd., Glen Echo. Prices depend on activity. 301-634-2222 or www.glenechopark.org.

HAUNTED HAPPENINGS -- 6-9 p.m. today through Sunday. Wheaton Regional Park celebrates Halloween with a carousel ride and a haunted train. 2000 Shorefield Rd., Wheaton. $5. 301-942-6703 or www.wheatontrainandcarousel.com.

TRICK OR TREAT -- 6 to 7:30 p.m. Monday. Store-to-store trick-or-treating, including candy and live music. Olde Towne Gaithersburg, Summit and Diamond avenues. Free. 301-258-6350 or www.gaithersburgmd.gov.

-- Compiled by Aruna Jain