Ferguson landslide, Natural geological formation in Merced River Canyon, California, US.

The Ferguson landslide is an active slide of rock and debris from Ferguson Ridge that covers the closed alignment of California State Route 140 in the Merced River canyon. The talus, roughly 320,000 tons of material, still falls onto the roadway. Traffic now passes on temporary bridges over the Merced River, using a grade left from the Yosemite Valley Railroad.

The slide began on April 29, 2006, when rock and debris came off Ferguson Ridge; the road stayed open under monitoring until it was closed permanently on May 28. A State of Emergency was declared for Mariposa County in June 2006. Two temporary bridges were built in August 2006, replaced in June 2008 by bridges able to carry vehicles longer than 28 feet.

The area is important for protecting the Limestone Salamander, an endangered species living in the Merced River canyon. Managing the site requires care to keep this rare animal safe in its natural home.

Temporary bridges with traffic signals manage one-way passage around the slide, with size limits for vehicles. Visitors should expect possible delays and follow all traffic instructions carefully.

The planned rock shed takes its name from Ferguson Ridge, the slope that failed in 2006. Caltrans chose this design over a tunnel in 2014. Phase 1, begun in early 2021, removes about 320,000 tons of talus and hangs cable drapery to limit further rockfall; the shed itself is a 675-foot (206 m) structure estimated at $285 million.