SR 99

VIDEO: A drone's-eye view of Bertha's work inside Washington's SR 99 tunnel
Damage to Big Bertha worse than previously thought
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VIDEO: Watch time-lapse of Highway 99 construction
Camera gives a live view of construction on Big Bertha's 12-story repair access pit
Tunnel-boring machine Big Bertha moves forward 2 feet in test run to see if blockage is fully removed
A steel pipe is what brought Big Bertha, the world's largest tunnel-boring machine, to a halt
No. 6 in 2013: Big Bertha digs in before being stopped in her tracks
Unstoppable Force, Immovable Object: Seattle's Big Bertha halted by mystery object