The Angeles National Forest, which closed Monday, will remain shuttered for a week due to "unprecedented and dangerous fire conditions within the region," the Forest Service said in a statement.
All general activity, which includes roads, trails, campgrounds and day-use sites, will be closed until Monday, Sept. 14.
State and county roads remain open for pass-through traffic, but officials emphasized that those roads are for pass-through traffic only.
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The closures have been implemented due to "a combination of extreme heat, dry conditions significant wind events, and firefighting resources that are stretched to the limit," the Forest Service for the Angeles National Forest said.
As of Monday, the Bobcat Fire continued to burn, growing to more than 4,800 acres, north of Azusa.
Officials said 2020 featured record visitor turnout, already making the year the busiest in the ANF's 112-year history.