WEST MIFFLIN, Pa. (AP) – A western Pennsylvania amusement park says its newest and biggest attraction is back up and running after a brief shutdown. A spokesman for Kennywood Park near Pittsburgh says the Steel Curtain roller coaster reopened Wednesday afternoon and has been operating smoothly ever since. It had been closed on Aug. 3 so workers could make some “adjustments.” The 4,000-foot-long coaster contains nine inversions, which park officials say is the most in North America, and the world’s tallest inversion at 197 feet. The park says “stoppages and periodic closures” will remain possible due to the “newness, complexity and record-breaking nature” of the ride. The park is located in West Mifflin, about 10 miles (16 kilometers) southeast of downtown Pittsburgh.