Friday marks ten years since the Oso landslide was triggered in Snohomish County.
At 10:37 a.m. on March 22, 2014, the once-forested hillside above Oso collapsed without warning in a massive landslide, destroying the Steelhead Haven neighborhood and killing 43 people.
Dozens of homes were wiped out when mud, rocks, trees, and debris roared down a hillside above the north fork of the Stillaguamish River.
A permanent memorial on Highway 530 will be publicly unveiled in a ceremony Friday morning.
It will honor the victims, survivors, and first responders of the mudslide — one of the deadliest in U.S. history.
After years of fundraising, the memorial received full funding from the Snohomish County Council in 2021, including $4.8 million.
Since 2014, a tribute has been going up in pieces. That fall, 43 trees were planted, one for each victim. Later, a row of bronze mailboxes was installed to represent the Steelhead Haven neighborhood destroyed by a wall of mud.
Washington State Department of Transportation workers observe the scene as crews work at the west side of the mudslide on Highway 530 near mile marker 37 in Arlington, Wash., on Sunday, March 30, 2014. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. Last night, the confirmed fatalities list was updated to 18, with the number of those missing falling from 90 to 30. (AP Photo/Rick Wilking, Pool)
Workers continue to dig through debris on foot and by excavator at the west side of the mudslide on Highway 530 near mile marker 37 on Sunday, March 30, 2014, in Arlington, Wash. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. (AP Photo/Rick Wilking, Pool)
A medical examiner enters the scene at the west side of the mudslide on Highway 530 near mile marker 37 in Arlington, Wash., on Sunday, March 30, 2014. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. Last night, the confirmed fatalities list was updated to 18, with the number of those missing falling from 90 to 30. (AP Photo/Rick Wilking, Pool)
Rescue and volunteer workers sort through debris and look for victims in the vast expanse of the west side of the mudslide on Highway 530 near mile marker 37 on Sunday, March 30, 2014. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. Last night, the confirmed fatalities list was updated to 18, with the number of those missing falling from 90 to 30. (AP Photo/Rick Wilking, Pool)
Rescue dog Nexus, muddy from working onsite, is decontaminated via hose after leaving the west side of the mudslide on Highway 530 near mile marker 37 on Sunday, March 30, 2014, in Arlington, Wash. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. (AP Photo/Rick Wilking, Pool)
In this photo, published Sunday, March 30, 2014, by the Seattle Times, Randy Fay, a volunteer rescue technician with Snohomish County's SnoHawk 10 rescue helicopter, helps Jetty Dooper, from the Netherlands, after a mudslide struck near Oso, Wash., on Saturday, March 22, 2014. Dooper, while visiting her friend Robin Youngblood who lived in the area, was caught in the slide when a wave of mud crashed into Youngblood's house. (AP Photo/Larry Taylor)
A Washington State Department of Transportation worker helps excavate many feet of mud at the west side of the mudslide on Highway 530 near mile marker 37 in Arlington, Wash., on Sunday, March 30, 2014. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. Last night, the confirmed fatalities list was updated to 18, with the number of those missing falling from 90 to 30. (AP Photo/Rick Wilking, Pool)
Workers use bits of plywood to cross over a small stream of muddy water flowing from the the west side of the mudslide on Highway 530 near mile marker 37 in Arlington, Wash., on Sunday, March 30, 2014. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. Last night, the confirmed fatalities list was updated to 18, with the number of those missing falling from 90 to 30. (AP Photo/Rick Wilking, Pool)
Search workers ride on a tracked vehicle Sunday, March 30, 2014, through the debris field of the massive mudslide that struck the community of Oso, Wash., on Saturday, March 22, 2014, as the search for victims continued near Darrington, Wash. (AP Photo/Ted S. Warren)
Two search and rescue dogs meet as they investigate a section of tree roots at the west side of the mudslide on Highway 530 near mile marker 37 on Sunday, March 30, 2014, in Arlington, Wash. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. (AP Photo/Rick Wilking, Pool)
Firefighters carefully cross a pool of water, using a fallen tree as a path, at the west side of the mudslide on Highway 530 near mile marker 37 on Sunday, March 30, 2014, in Arlington, Wash. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. (AP Photo/Rick Wilking, Pool)
Firefighters navigate through downed trees as they carry shovels in the muck at the west side of the mudslide on Highway 530 near mile marker 37 on Sunday, March 30, 2014, in Arlington, Wash. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. (AP Photo/Rick Wilking, Pool)
Rescue dog Nexus, muddy from working onsite, waits to be decontaminated via hose at the west side of the mudslide on Highway 530 near mile marker 37 in Arlington, Wash., on Sunday, March 30, 2014. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. Last night, the confirmed fatalities list was updated to 18, with the number of those missing falling from 90 to 30. (AP Photo/Rick Wilking, Pool)
An American flag pulled from the debris hangs in the staging area at the west side of the mudslide on Highway 530 near mile marker 37, in Arlington, Wash., on Sunday, March 30, 2014. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. Last night, the confirmed fatalities list was updated to 18, with the number of those missing falling from 90 to 30. (AP Photo/Rick Wilking, Pool)
A weary searcher bows his head as he walks out of the west side of the mudslide site with a small saw on Highway 530 near mile marker 37 in Arlington, Wash., on Sunday, March 30, 2014. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. Last night, the confirmed fatalities list was updated to 18, with the number of those missing falling from 90 to 30. (AP Photo/Rick Wilking, Pool)
Rescue dog Nexus, muddy from working onsite, is decontaminated via hose after leaving the west side of the mudslide on Highway 530 near mile marker 37 on Sunday, March 30, 2014, in Arlington, Wash. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. (AP Photo/Rick Wilking, Pool)
A worker, weary from the day's work, re-enters the site at the west side of the mudslide on Highway 530 near mile marker 37 in Arlington, Wash., on Sunday, March 30, 2014. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. Last night, the confirmed fatalities list was updated to 18, with the number of those missing falling from 90 to 30. (AP Photo/Rick Wilking, Pool)
Rescue dog Nexus, muddy from working onsite, strolls the staging area at the west side of the mudslide on Highway 530 near mile marker 37, in Arlington, Wash., on Sunday, March 30, 2014. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. Last night, the confirmed fatalities list was updated to 18, with the number of those missing falling from 90 to 30. (AP Photo/Rick Wilking, Pool)
Rescue dog Nexus, muddy from working onsite, waits to be decontaminated via hose after leaving the west side of the mudslide on Highway 530 near mile marker 37 on Sunday, March 30, 2014, in Arlington, Wash. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. (AP Photo/Rick Wilking, Pool)
A weary searcher heads out of the west side of the mudslide site with a small saw on Highway 530 near mile marker 37 in Arlington, Wash., on Sunday, March 30, 2014. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. Last night, the confirmed fatalities list was updated to 18, with the number of those missing falling from 90 to 30. (AP Photo/Rick Wilking, Pool)
Orange-clad search workers look through a muddy area Sunday, March 30, 2014, near Darrington, Wash., at the bottom end of the massive mudslide that struck the community of Oso, Wash. (AP Photo/Ted S. Warren)
Bellevue Fire Public Information Officer, Richard Burke talks with the media at the west side of the mudslide on Highway 530 near mile marker 37 on Sunday, March 30, 2014. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. Last night, the confirmed fatalities list was updated to 18, with the number of those missing falling from 90 to 30. (AP Photo/Rick Wilking, Pool)
Snohomish County Technical Rescue workers clear bits of plywood and debris from the mud at the west side of the mudslide on Highway 530 near mile marker 37 on Sunday, March 30, 2014, in Arlington, Wash. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. (AP Photo/Rick Wilking, Pool)
Workers search by hand and with heavy equipment Sunday, March 30, 2014, near Darrington, Wash., for victims of the Saturday, March 22 mudslide that hit the nearby community of Oso, Wash. (AP Photo/Ted S. Warren)
Snohomish County firefighters walk through the mud on a plywood path at the west side of the mudslide on Highway 530 near mile marker 37 on Sunday, March 30, 2014, in Arlington, Wash. Periods of rain and wind have hampered efforts the past two days, with some rain showers continuing today. (AP Photo/Rick Wilking, Pool)