During the 6.9 Loma Prieta earthquake , the double-decked Cypress Street Viaduct on I-880 between I-80 and the 14th Street exit collapsed , crushing cars and killing 42 people . Traffic on the MacArthur Maze headed towards I-880 was re-routed to I-580 and I-980 , and ramps at both ends of the viaduct leading to the former Cypress Structure were signed for local traffic access to Cypress Street
Loma Prieta earthquake
1989 Loma Prieta earthquake
MacArthur Maze