Photos: Earth Hour 2015

A combo photograph showing (top) Saint Peter’s Basilica is seen lit before lights were turned off and (bottom) Saint Peter’s Basilica stands in darkness after lights were turned out for one hour to mark Earth Hour, Vatican City, 28 March 2015.   (CLAUDIO PERI / EPA)

epa04684252 A combo image which shows a general view of the Cibeles square and Puerta de Alcala in the background with their lights switched off during the ‘Earth Hour’ in Madrid, Spain, 28 March 2015.  (VICTOR LERENA / EPA)

A combo photograph showing (L) the Palace of Culture and Science lit and (R) the Palace standing in the darkness after lights were turned off for one hour to mark the Earth Hour in Warsaw, Poland, 28 March 2015.  (RADEK PIETRUSZKA / EPA)

People sit around candles they lit during the ‘Earth Hour’ event in Guatemala City, Guatemala, 28 March 2015.   (Esteban Biba / EPA)

A composite photo of two images with lights on (top) and off (below) showing the National Stadium (Bird’s Nest) in Beijing city, China, 28 March 2015.  (WU HONG / EPA)

A combo picture taken on March 28, 2015 in the Ukrainian capital of Kiev shows Gulliver building being submerged into darkness for the Earth Hour environmental campaign.   (SERGEI SUPINSKY / AFP/Getty Images)

A combo picture taken on March 28, 2015 in Paris shows the Eiffel Tower being submerged into darkness for the Earth Hour environmental campaign.  (JACQUES DEMARTHON / AFP/Getty Images)

This combination picture of two photographs shows the Grand Palace before (top) and after (bottom) its lights were turned off to mark Earth Hour in Bangkok on March 28, 2015.   (PORNCHAI KITTIWONGSAKUL / AFP/Getty Images)

This combination picture shows the Taipei 101 building before and during Earth Hour in Taipei on March 28, 2015.  (SAM YEH / AFP/Getty Images)

A combo picture taken on March 28, 2015 in Belgrade shows Serbian National Assembly building being submerged into darkness for the Earth Hour environmental campaign.   (ANDREJ ISAKOVIC / AFP/Getty Images)

A combination photo shows the Kremlin being submerged into darkness for the Earth Hour environmental campaign in central Moscow on March 28, 2015.   (DMITRY SEREBRYAKOV / AFP/Getty Images)

In this two photo combination picture, the Indian Presidential Palace is seen lit, top, and then the same location in darkness when the lights are turned out for one hour to mark Earth Hour, in New Delhi, India, Saturday, March 28, 2015.   (Altaf Qadri / AP)

Dancers wearing neon clothes perform during an event to mark Earth Hour at a park in Manila on March 28, 2015.   (TED ALJIBE / AFP/Getty Images)

A combination of two pictures shows Malaysia’s landmark Petronas Twin Towers in Kuala Lumpur before (top) and after the lights were switched off (bottom) for earth hour on March 28, 2015.  (MOHD RASFAN / AFP/Getty Images)

A combination of two pictures taken on March 28, 2015 shows Palace of the Grand Dukes of Lithuania before and during the annual Earth Hour event in Vilnius, Lithuania.   (PETRAS MALUKAS / AFP/Getty Images)

Employees of the Jumeirah Messilah Beach Hotel pose behind candles during the Earth Hour on March 28, 2015 in Kuwait City.  (YASSER AL-ZAYYAT / AFP/Getty Images)

This combo picture shows Yokohama city’s Landmark Tower (L) and ferris wheel (R) being submerged into darkness for the Earth Hour environmental campaign in Yokohama, suburban Tokyo on March 28, 2015.   (YOSHIKAZU TSUNO / AFP/Getty Images)

This combination image shows the Colosseum illuminated and with the lights turned off to mark “Earth Hour” in Rome on March 28, 2015.  (TIZIANA FABI / AFP/Getty Images)

A combo picture taken on March 28, 2015 in Athens shows the ancient Temple of Parthenon atop the Acropolis hill being submerged into darkness for the Earth Hour environmental campaign.   (ANGELOS TZORTZINIS / AFP/Getty Images)

A combination picture shows the Brandenburger Gate in Berlin before and during the global climate change awareness campaign “Earth Hour” on March 28, 2015.   (JOHN MACDOUGALL / AFP/Getty Images)

People light candles during Earth Hour environment campaign at the Jardin Plaza mall in Cali, Valle del Cauca department, Colombia, on March 28, 2015.   (LUIS ROBAYO / AFP/Getty Images)

A combo picture taken on March 28, 2015 in central London shows the Houses of Parliament being submerged into darkness for the Earth Hour environmental campaign.   (GLYN KIRK / AFP/Getty Images)

A combo picture taken on March 28 2015 shows the Niteroi Contemporary Art Museum (MAC) being submerged into darkness for the Earth Hour environmental campaign, in Niteroi, a neighbouring city of Rio de Janeiro, Brazil, on March 28, 2015.  (YASUYOSHI CHIBA / AFP/Getty Images)

A combo picture taken on March 28, 2015 in Brussels shows theGrand-Place - Grote Markt being submerged into darkness for the Earth Hour environmental campaign.   (NICOLAS MAETERLINCK / AFP/Getty Images)

A combination photo shows the Belarusian National Library being submerged into darkness for the Earth Hour environmental campaign in Minsk on March 28, 2015.  (SERGEI GAPON / AFP/Getty Images)

A combination photo shows the Sydney Harbour Bridge and Opera House being plunged into darkness for the Earth Hour environmental campaign, among the first landmarks around the world to dim their lights for the event on March 28, 2015.   (PETER PARKS / AFP/Getty Images)