Old Stone House will be the site of "A Civil War Christmas" from 9 a.m. to 5 p.m. Saturday and 9 a.m. to 3 p.m. Sunday. This free public program highlights the traditions, music and culture of the 19th century. Guests can visit with soldiers at home and in camp, and meet the wives, children and men who endured the holiday season during a trying time in American history. The Old Stone House is owned and managed by Slippery Rock University. For information, call 724-738-4964.

Butler County Heritage Center, 119 W. New Castle St., will display two model railroads Sunday afternoons through Jan. 4. Hours will be noon until 4 p.m. In addition to a small, new train display, the Heritage Center is also home to the Jay Bee Miniature Circus, Austin and Bantam cars as well as the "jeep," which was produced in the city of Butler, and exhibits about Pullman-Standard, the steel, oil and glass industries. Museum admission is $5 for adults, $2 for children ages 5 to 17, and free for those younger than 5. Call 724-283-8116.

Lowrie/Shaw House, built in 1828 by Butler's only United States senator, is open through the end of the year on Mondays, Wednesdays and Fridays (closed Dec. 24). Hours are noon until 4 p.m., with the last tour beginning at 3 p.m. Admission is $3 for adults, $1 for ages 5 to 17, and free for ages 5 and under. The house museum is located at 123 W. Diamond Street, directly behind the Butler County Courthouse. Call 724-283-8116 or visit the Web site, www.butlerhistory.com.

Harmony Museum on Mercer Street in Harmony, representing the town founded in 1804 by pacifist German Lutheran Separatists and their Harmony Society, hosts its annual Candelight Christmas with dinner on Sunday. Rooms have been decorated for the Christmas season. The annual Yobp-Eckstein log house village and toy railroad display is a special seasonal attraction in the Wagner House museum annex. Call 724-452-7341.

<B>Carnegie Museum of Natural History</B>, 4400 Forbes Ave. in Oakland, is exhibiting "Born of Fire: The Life and Pottery of Margaret Tafoya" through Jan. 4. The first East Coast exhibit of the works of this Pueblo potter features more than 75 pieces, with additional works by her mother and descendants. "Dinosaurs in Their Time" continues. Hours are 10 a.m. to 5 p.m. Tuesdays through Saturdays, with additional hours until 8 p.m. Thursdays, and noon to 5 p.m. Sundays. Closed major holidays. Admission, which includes the Carnegie Museum of Art, is $15 for adults, $12 for senior citizens, and $11 for students and children age 3 and older, and free for members and children younger than 3. Call 412-622-3131 or visit the Web site, www.carnegiemnh.org.<B>Phipps Conservatory and Botanical Gardens</B> in Schenley Park is displaying some Donald M. Robinson photographs of the Chihuly glass that was exhibited at Phipps last year. The photography will be shown through Jan. 22. Phipps is open daily from 9:30 a.m. to 5 p.m. and until 10 p.m. on Fridays. Admission is $10 for adults, $9 for seniors age 62 and older and students with ID, and $7 for children ages 2 to 18. Phipps members and children under 2 are admitted free. Call 412-622-6914.<B>National Aviary</B>, 700 Arch St., will offer one free child admission with the purchase of an adult admission each Sunday in December. Also, Saturdays with Santa and his penguin helpers are planned from 11 a.m. to 2 p.m. Saturday and Dec. 20. This extra program is $10 per child; adults pay regular $9 admission. Hours at the Aviary will include being open from 10 a.m. to 3 p.m. Dec. 24, closed Dec. 25, and open 10 a.m. to 3 p.m. Dec. 31 and 10 a.m. to 5 p.m. Jan. 1. Regular hours are 10 a.m. to 5 p.m. daily except Christmas Day. Regular admission is $9 for adults; $8 for senior citizens; $7.50 for children ages 2 to 12; and free for children younger than 2. Call 412-323-7235 or visit the Web site, www.aviary.org.<B>Carnegie Science Center</B>, One Allegheny Ave. on the North Side, is offering visitors the child rate of admission of $10 Mondays through Fridays through Dec. 24, with the opportunity to add an Omnimax movie or matinee laser show for $5. The traveling exhibition "Hubble Space Telescope: New Views of the Universe," continues through Jan. 12. Regular hours are 10 a.m. to 7 p.m. Fridays and Saturdays and from 10 a.m. to 5 p.m. Sundays through Thursdays; closed holidays. Regular admission to the science center is $14 for adults and $10 for senior citizens age 62 and older and children 3 to 18. Parking is $3; people not visiting the science center pay more. Call 412-237-3400.<B>Heinz History Center</B>, 1212 Smallman St., features its new exhibit, "Pittsburgh: A Tradition of Innovation," tracing Western Pennsylvania's imprint on the world. Hours are 10 a.m. to 5 p.m. daily, except holidays. Admission is $9 for adults, $7 for senior citizens older than 61, $5 for students with ID and for children ages 6 to 18, and free for children younger than 6. Call 412-454-6000.

<B>Compass Inn Museum, </B>Route 30 in Laughlintown, will host Candlelight Tours of the historical stagecoach stop decorated for the season from 3 to 7 p.m. Saturday and Sunday. Admission is $9 for adults, $6 for students and free for children age 5 and younger. Call 724-238-4983 or visit the Web site, www.compassinn.com. Ligonier's Festival of Lights takes place through Sunday between noon and 7 p.m. daily. Admission to the festival is $4 for adults and $1 for children. Call 724-238-6818 or visit www.ligonierhistoricalsociety.org.