PORTLAND, Ore. — Residents of more than 400 homes in a prime eclipse-viewing location in Oregon were ordered to evacuate Friday because of a rapidly growing wildfire that had already closed access to a portion of a wilderness area and a regional highway.

The late afternoon order threatened to create more tie-ups on rural and narrow roads already expected to be burdened with up to 200,000 visitors coming to the area from all over the world to watch Monday’s total solar eclipse. About 1 million people are expected in Oregon, where the moon’s shadow first makes landfall in the continental U.S.

The nearly 11-square-mile wildfire in the Deschutes National Forest was about six miles west of the town of Sisters, which sits on the southern edge of the 70-mile swath of Oregon where the moon will completely blot out the sun.