The Lassen Volcanic National Park is visited by more than 350,000 people every year. Incorporating more than of hiking trails, it is visited by people looking to hike or backpack during the summers. Popular winter activities include snowshoeing and backcountry skiing. As the second-tallest volcano in Northern California, trailing only Mount Shasta, Lassen Peak is frequently visited by climbers and hikers from around the world. The summit opens for use most years near the end of June, remaining in use until heavy snow falls in October or November. After a 9-year-old boy died from a collapsed retaining wall along the summit trail on July 29, 2009, the path closed for six years for construction, reopening in 2015.