High Quality Content by WIKIPEDIA articles! Chantry Flat is a designated "Recreation Area" within the Angeles National Forest, about three miles (5 km) into Big Santa Anita Canyon, and is closely associated with the towns of Arcadia and Sierra Madre, CA. The flat itself houses a large public picnic area, and is the starting point for several historic trails of the San Gabriel Mountains, including the 28.5-mile (45.9 km) Gabrielino Trail. The US Forest Service estimates the road to Chantry as the third busiest entry into the Angeles, next to CA State Highways 2 and 39 .