Old Stone House will be the site of tours from 10 a.m. to 5 p.m. Saturdays and noon to 5 p.m. Sundays through October. Halloween and perhaps Christmas events will be planned. Admission is free but donations are accepted for operation of the historical site. The house at the intersection of Routes 8, 173 and 528, 12 miles north of Butler, is owned and operated by Slippery Rock University. Call 724-738-4964 to confirm hours or make reservations for private tours.

Butler County Heritage Center, 119 W. New Castle St., featuring the new exhibit, "100 Years of Steel in Butler County" is open from noon to 4 p.m. Mondays and Fridays through September, excluding legal holidays. The exhibit of the Jay Bee Miniature Circus continues. Admission is $5 for adults, $2 for children ages 5 to 17, and free for children younger than 5. Call 724-283-8116.

Harmony

Museum represents the town founded in 1804 by pacifist German Lutheran Separatists, and their Harmony Society. The area was resettled in 1815 when Mennonite "second founder" Abraham Ziegler bought the society's holdings. The museum offers guided tours from 1 to 4 p.m. daily except Mondays and holidays; reservations suggested for weekends and required for groups. Call 724-452-7341 or 888-821-4822, e-mail hmuseum@zoominternet.net., or visit the Web site, www.harmonymuseum.org.

Passavant House and Buhl House, historic house museums of the Zelienople Historical Society, at 243 and 221 S. Main St. in Zelienople, are open for regularly scheduled tours beginning at 1 and 2:30 p.m. Wednesdays and Saturdays through September. Admission, which covers both houses, is $5 for adults, $3 for students. Call 724-452-9457.

<B>Heinz History Center</B>, 1212 Smallman St., in celebration of Pittsburgh's 250th birthday, is displaying "Pittsburgh At 250," honoring our region's historic anniversary celebrations in 1858, 1908, 1958 and 2008. Each section includes artifacts and documents from the anniversary celebration set against a panoramic view of the city from that time period. Featured artifacts include commemorative medals and souvenirs, as well as books, programs and special publications. The display will continue through early 2009. 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>Carnegie Museum of Natural History</B>, 4400 Forbes Ave. in Oakland, has opened the final phase of "Dinosaurs in Their Time," featuring the return of the museum's Tyrannosaurus rex, which is joined by a second T. rex, with the two frozen in a confrontation. "Insects, Ink & Inklings: Illustrations by Jane Hyland" runs through Nov. 1. Admission is $15 for adults, $12 for senior citizens, $11 for children ages 3 to 18 and full-time students with ID, and free to children younger than 3 and Carnegie Museums members. Hours are 10 a.m. to 5 p.m. Tuesdays through Saturdays, 10 a.m. to 8 p.m. Thursdays, noon to 5 p.m. Sundays. Call 412-622-3131 or visit the Web site, www.carnegiemnh.org.

<B>Old Economy Village</B>, Route 65, Ambridge, will host Erntefest, a traditional German harvest festival, from 10 a.m. to 4:30 p.m. Saturday. Visitors will have a chance to learn how to make cheese, sausage, butter, apple schnitz, cider, ginger beer and a variety of other traditional fall foods. There will be broom making, meat smoking, coopering, bee keeping, wine making and beer brewing, all activities that would have been done by members of the Harmony Society who lived there in the years before the Civil War. Old-time games will be played, too, and food will be available. Admission is $8 for adults, $5 for children ages 4 to 17, and free for children younger than 4. Call 724-266-4500 or visit the Web site, www.oldeconomyvillage.org.