As part of his escape plan after assassinating Martin Webb, the anarchist Zapata hired Gabriel Panatello and four of his associates to cause car accidents at key points throughout the city. Pan's friend Doogie crashed his car at Cahuenga on U.S. 101, which - combined with the other three - resulted in a virtual standstill on all the major freeways across the city. Some time later, Jack Bauer, stuck on the 101 en route to the Staples Center, had Ryan Chappelle send a helicopter to pick him up from the side of the road.
After sighting Zapata at the Staples Center, Jack pursued him to a barranca near the intersection of the 101 and Interstate 110, and ultimately shot and killed him. (Chaos Theory)
The real life U.S. Route 101 is seen in Day 1: 9:00am-10:00am, as Jack drives towards 21500 Riverside Drive, passing a sign for the San Diego Freeway. He is driving in the right direction for the real Riverside Drive, and tells Nina that he is getting off the freeway to drive along it. However he also tells her he is coming up on Culver, which is nowhere near the 101.
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