People threatened to exploit the symbolism of a car-free 405 by riding bikes on it and using it for other environmentally friendly activities during the first Carmageddon shutdown last year.

But, save for a few random acts of planking and dining, the mass transportation demonstrations that some cops feared didn't materialize.

This weekend the 405 shutdown is back for Carmageddon II. And once again …

… authorities are warning you action-sports heroes to stay away from the freeway.

The 405 will be closed from the 10 to the 101 through West L.A. and the Sepulveda Pass from as early as 7 p.m. Friday at least through the end of Sunday, according to the CHP and Metro.

The closure will make way for the final destruction of the old Mulholland Bridge.

CHP Capt. Harsh Yourmellow Assistant Chief Calvin Aubrey is warning fun-lovers to stay away from this concrete playground. He says:

Drivers, pedestrians, bicyclists, skateboarders, take note: If you access the closed section of the 405 you will be breaking the law, and we will take appropriate action.

We assume that applies to plankers and diners as well.

Credit: teamtigerawesome.tumblr.com

Credit: teamtigerawesome.tumblr.com

But if you do decide to do this — and we recommend you do not — send us photos.

[@dennisjromero / djromero@laweekly.com / @LAWeeklyNews]

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