Lights will flick off throughout the Twin Cities on Saturday night as civic leaders join a global movement to conserve energy.

During Earth Hour, iconic monuments such as Paris’ Eiffel Tower, London’s House of Parliament and New York’s Empire State Building will go dark when the clock strikes 8:30 p.m. local times. Minnesota’s State Capitol, along with dozens of other businesses and local institutions plan, to participate by shutting off all nonessential lighting for that hour.

For the event, billed as “the world’s largest voluntary action for the environment,” the cities of Minneapolis, St. Paul and Eden Prairie are encouraging residents to join the effort.

At least two dozens locations in St. Paul — including Xcel Energy Center, Union Depot and Rice Park — have pledged action. Beyond Saturday, the movement asks people to make small changes to aid the environment: eating less meat and reducing energy waste.

The 10th annual event, organized by the World Wildlife Fund, draws participants from 178 countries and territories with the goal of shining “a light on climate action,” organizers say.