After the white-shelled roof of the Sydney Opera House fell dark, after Taiwan's skyscrapers dimmed and Beijing's Forbidden City became, well, a little more forbidding - it was Moscow's turn to turn out the lights as Saturday's global Earth Hour event rolled around to Europe.
Millions of people worldwide were switching off lights and appliances for an hour from 8:30 p.m. in a gesture to highlight environmental concerns and to call for a binding pact to cut greenhouse gas emissions. This year's was the fourth annual Earth Hour, organized by the World Wildlife Fund.
As each time zone reaches the appointed hour, skylines go dark and landmarks dim, from a Manila shopping mall to the Eiffel Tower in Paris and the Empire State Building in New York.
Officials in Russia said they hoped to beat last year's national participation figure of more than 6 million people in 20 cities across the vast country. Far East spots like Kamchatka and Siberia's Irkutsk joined their Asian neighbors in switching off before Moscow.
Restaurants in Vladivostok held a so-called Candle Evening, promoting Earth Hour as a chance for romance.
"One in three Russians heard of Earth Hour last year, and we're striving to beat that," said Aleksei Knizhnikov, who heads the WWF's oil and gas ecological program in Russia.
Some 4,000 cities in more than 120 countries - starting with New Zealand - were voluntarily switching off Saturday to reduce energy consumption, though traffic lights and other safety features would be unaffected, organizers said.
"We have everyone from Casablanca to the safari camps of Namibia and Tanzania taking part," said Greg Bourne, CEO of World Wildlife Fund in Australia, which started Earth Hour in 2007 in Sydney before it spread to every continent.
Organizers say there's no uniform way to measure how much energy is saved worldwide during the event, but hope global participation will send a message to leaders that people worldwide are worried about global warming.
"What we're still looking for in this coming year is a global deal that encourages all countries to lower their emissions," said Andy Ridley, a WWF worker in Sydney who came up with the idea of Earth Hour in a pub with friends.
He said he hoped this year's event would inspire world leaders to strive for a climate change deal that would hold nations to rules for reducing greenhouse gas emissions - blamed for global warming.
"China is going to have to be a big part of that, but so is every other major economy," he said.
This year, China participated in Earth Hour for the second time, with the giant panda Mei Lan kicking off the event in 30 cities by walking onto a platform amid dimming lights in her enclosure at the Chengdu Panda Breeding Research Center in the southwestern province of Sichuan, said Chris Chaplin of WWF in China.
Lights were also turned off in Beijing's landmark imperial palace known as the Forbidden City.
Some 1,000 towns and cities in the Philippines switched off their lights, and a rock concert and street party were held at a Manila Bay mall complex, according to WWF-Philippines. The country's Roman Catholic bishops, meanwhile, urged the faithful to preserve natural resources in prayers read church-run radio from 8:30 p.m.
"The failure of today's people to care for the Earth's resources is akin to stealing the future of the coming generations," Manila Archbishop Gaudencio Rosales said in a statement.
Taiwan's Presidential Palace and at least 20 Taipei skyscrapers went dark, while hundreds of Taiwanese placed candles beside a Taiwan map formed by energy-saving LED lights at a square outside the city hall.
Last year, some 88 cities took part in Earth Hour, which is backed by the United Nations as well as global corporations, nonprofit groups, schools, scientists and celebrities.
Meanwhile, European cities were gearing up to power down. Germany planned to have Berlin's Brandenburg Gate and the Cologne Cathedral go dark, and Amsterdam was cutting the lights at most city buildings including Schiphol Airport, Artis Zoo and the Amsterdam Arena.
In Paris, the Eiffel Tower was to plunge into darkness.
More than 70 premises in Moscow were scheduled to switch off, including the mayor's office and the iconic Luzhniki Stadium - though already 40 Russian towns and cities further east had already gone dark.