Set in wooded surroundings, this impressive center serves to orient visitors to the park through its detailed exhibits on the geologic history of the volcano, a timeline of events surrounding the recent eruption, and a dramatic, live-footage movie This Place in Time (22min). A seismograph allows visitors to record mini-earthquakes they can create themselves by stomping their feet.From the visitor center, Route 504 continues east 48mi. Known as the Spirit Lake Memorial Highway, the road was built between 1992-95, on a ridge following the valley of the Toutle River, with clear views-weather permitting-of Mt. St. Helens on the eastern horizon. About 5.5mi from the visitor center, a new bridge spans the Toutle, just below the confluence of the north and south forks of the river. It replaces a bridge destroyed by 1980 mudflows and the debris they carried. At Mile 16 the highway begins to roughly parallel the North Fork of the Toutle, and at Mile 24.5, it crosses Hoffstadt Creek Bridge, spanning a gorge that plunges 370ft below it. Now devastation from the eruption becomes apparent; trees in this area were fatally scorched by the heat. Farther on begins the blow-down zone-where trees were actually leveled by the blast.