Why there will be people dancing on the side of L.A. City Hall on Tuesday

A dancer rehearsing for "La La Land" Day at City Hall. (via James Adamson, Drop Media and BANDALOOP via Sozo Artists.)

On Tuesday morning, downtown L.A. is going Hollywood.

Mayor Eric Garcetti will formally declare April 25 "La La Land" Day with a celebration at City Hall. The date coincides with the DVD and Blu-ray release of the movie, which was filmed across Los Angeles.

The festivities begin Tuesday at 8 a.m., with the mayor’s ceremony slated to start at 8:30 a.m.

A jazz band will kick things off, followed by aerial dancers from Bandaloop performing a dance medley off the side of City Hall.

Director Damien Chazelle, composer Justin Hurwitz, production designers David Wasco and Sandy Reynolds-Wasco, choreographer Mandy Moore and jewelry designer Kyle Chan are all expected to attend.

If you were driving downtown this morning – say, if you were on your way to work at the L.A. Times building down the street – you might have caught them rehearsing.

From the sound of it, they’ll be dancing to “Another Day of Sun,” the opening song from the “La La Land” soundtrack.

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