Rainbow-clad revelers in the millions will gather in Manhattan on Sunday for the annual NYC Pride March, which steps off at noon from Fifth Avenue and 26th Street.

Billed by organizers as the biggest LGBTQ demonstration and celebration in the world, the daylong event will feature some 150,000 marchers and more than 400 floats.

Marchers will head south on Fifth Avenue to Eighth Street, then turn west and onto Christopher Street before heading north on Seventh Avenue to 23rd Street.

Driving below 33rd Street or north of Houston Street will remain an effort in futility until Monday.

All crosstown traffic along the march route will be prohibited until midnight, according to the NYPD.

For those who can’t brave the throngs — and thongs! — in person, ABC will broadcast the march from noon to 4 p.m., and it will be live-streamed on YouTube.