SEATTLE - State Route 520 near the Washington Park Arboretum will be closed this weekend as crews remove an old westbound off-ramp spanning the highway.
The closure affects both directions of SR 520 between 92nd Avenue Northeast and Montlake Boulevard, the Washington State Department of Transportation said.
All associated on-and-off ramps with also be closed, though the on-ramp from Montlake Boulevard to Westbound SR 520 will remain open.
The new floating bridge's bicycle and pedestrian path will also be closed in both directions.
Crews closed the highway late Friday night. They estimate it will remain closed until 5 a.m. Monday morning.
The off-ramp is one of several ramps that were built for the proposed R.H. Thomson Expressway in the 1960s and never used, according to Historylink.
The project was meant to connect Seattle's Central District to Interstate 5, but was canceled amid community protests and environmental concerns.
The project was scrapped by the City Council in 1971. The unused ramps, often called "ramps to nowhere", have since become popular with summertime swimmers.
The state announced plans to tear down the ramps in 2013. Crews have been removing pieces of the ramps for months.
The off-ramp being removed this weekend crosses over SR 520 and is being closed due to safety concerns for drivers.