• A Walk on a Trail. Schenley Park, Steve Faloon Trail, Circuit Drive at Westinghouse Pond, Oakland. Dogs on leashes welcome. Less than 2 miles. 10 a.m. May 4. $15, kids $10. Benefits Steve Faloon Bone Marrow Fund. 412-561-7161.

• The Sierra Club's Allegheny Group is sponsoring the following activities on April 27 unless otherwise indicated:

-- Cookout with hiking or canoeing nearby, along the Allegheny River near Lock 6, April 26. Meet at 10 a.m. at the Bob Evans Restaurant in Harmar. Call 412-828-5154.

-- Fourth quarter, Rachel Carson Trail. For experienced hikers only. Call 412-826-0519.

-- Loop hike in and above the gorge of the Conemaugh River from Robinson, over Chestnut Ridge and along Packsaddle Gap North. Call 412-362-5567.

-- 8-mile loop hike near the summit area of Laurel Mountain, near Route 30 in Forbes State Forest. Call 412-576-0849.

-- Seldom Seen Greenway, Beechview. Meet at 1:30 p.m. at the far end of the parking lot at Brashear High School, 590 Crane Ave., Beechview. Call 412-341-9367 or 412-922-3951.

• Still Mountain T'ai Chi and Chi Kung are offering free demonstrations and workshops from 10 a.m. to noon April 26 in Bird Park, Mt. Lebanon, in recognition of World T'ai Chi Day. Call 412-480-9177.

• Excela Health is sponsoring a low-impact aerobics class from 5:30 to 6:30 p.m. Thursdays beginning May 1 or Mondays beginning May 5 at the Well Being Center for Mind/Body Health, Medical Commons One, Westmoreland Hospital, Greensburg. Call 1-877-771-1234.