Parking Lot #2 (in red) is closest to Young Hall, Paul Boyer Hall & Molecular Sciences Building.
An alternative is Lot #9 (in green).
Below are driving directions to each.

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From LAX to UCLA Lot #2:
Take Century Blvd to the 405 Fwy North.
Take the Wilshire Blvd. exit, going East.
Turn Left (N) on Glendon Avenue
Turn Right (E) on Lindbrook Drive.
Turn Left (N) on Hilgard.
Westholme is the 2nd signal.
Turn Left at Westholme onto the UCLA campus.
Go to the Parking Kiosk on your right.
Parking Lot 2 is directly on your Left.
Parking is $8 per entry and is limited.

From LAX to UCLA Lot #9:
Take Century Blvd to the 405 Frwy North.
Take the Wilshire Blvd. exit, going East.
Turn Left (N) on Westwood Blvd.
Go to the Parking Kiosk in center of Westwood Blvd.
Get a pass at the Parking Kiosk.
Turn right (E) at Charles E. Young Drive South (next signal).
Parking Lot 9 is almost immediately up a ramp to your left.
Parking is $8 per entry and is limited.