People walk at a scenic viewpoint area at Badlands National Park as the spread of the coronavirus disease (COVID-19) continues, where visitors centers and entrance stations are closed but roads, campgrounds and trails remain open near Wall, South Dakota, U.S., April 16, 2020. REUTERS/Shannon Stapleton

A sign informing visitors that Mulholland Scenic Overlook is closed during the coronavirus disease (COVID-19) outbreak, in Los Angeles, California, April 5, 2020. REUTERS/Lisa Girion

Men wearing protective masks stand as people hike along a section of the Great Wall in Badaling in Beijing, on its first day of re-opening after the scenic site's coronavirus related closure, China, March 24, 2020. REUTERS/Thomas Peter

A woman wearing a protective mask hikes along a section of the Great Wall in Badaling in Beijing, on its first day of re-opening after the scenic site's coronavirus related closure, China, March 24, 2020. REUTERS/Thomas Peter

A man wearing a protective mask poses for a picture at the Great Wall in Badaling in Beijing, on its first day of re-opening after the scenic site's coronavirus related closure, China, March 24, 2020. REUTERS/Thomas Peter

A person wearing a protective mask hikes along a section of the Great Wall in Badaling in Beijing, on its first day of re-opening after the scenic site's coronavirus related closure, China, March 24, 2020. REUTERS/Thomas Peter

Czech painter and scenic designer Martin Cerny stands in front of a newly installed curtain during a general renovation of Prague's State Opera building in Prague, Czech Republic, December 19, 2019. REUTERS/David W Cerny

Czech painter and scenic designer Martin Cerny poses in front of a newly installed curtain during a general renovation of Prague's State Opera building in Prague, Czech Republic, December 19, 2019. REUTERS/David W Cerny

Windmills line a hillside in Palm Springs, California, U.S., November 29, 2019. REUTERS/Lucy Nicholson

Windmills line a hillside in Palm Springs, California, U.S., November 29, 2019. REUTERS/Lucy Nicholson

Clouds hang over the mountains on a rainy day near Holzkirchen, Germany, November 28, 2019. REUTERS/Michael Dalder

Clouds surround an autumnal tree on a rainy day near Holzkirchen, Germany, November 28, 2019. REUTERS/Michael Dalder

Clouds surround an autumnal tree on a rainy day near Holzkirchen, Germany, November 28, 2019. REUTERS/Michael Dalder

The U.S. Capitol building is seen in a reflection on Capitol Hill in Washington, U.S., November 27, 2019. REUTERS/Loren Elliott

The sun rises over a smoldering landscape that was burned by a wildfire dubbed the Cave Fire, burning in the hills of Santa Barbara, California, U.S., November 26, 2019. REUTERS/David McNew

The sun sets over the Saint Isaac's Cathedral in Saint Petersburg, Russia November 25, 2019. REUTERS/Anton Vaganov TPX IMAGES OF THE DAY

A patch of snow is covered for tourists to use with slides later in the season on the Tsanfleuron Glacier near Les Diablerets in Switzerland, September 13, 2019. Picture taken September 13, 2019. REUTERS/Denis Balibouse

The Eiger, Guggi and Giesen Glaciers are pictured near the Jungfrau in the Swiss Alps in Wengen, Switzerland August 27, 2019. Picture taken August 27, 2019. REUTERS/Denis Balibouse

A Jungfraubahn train is pictured in front of the Eiger Glacier in Wengen, Switzerland August 27, 2019. Picture taken August 27, 2019. REUTERS/Denis Balibouse

The Aurora Borealis is visible from a plane at 37,000 feet above the Labrador Sea and the North Atlantic Ocean between Canada and Greenland, November 22, 2019. Picture taken November 22, 2019. REUTERS/Jim Urquhart

Roseate Spoonbills are seen on the shores of the Paraguay River, in Ita Enramada, Paraguay November 23, 2019. REUTERS/Jorge Adorno

Egrets are seen next to a discarded tire on the shores of the Paraguay River, in Ita Enramada, Paraguay November 23, 2019. REUTERS/Jorge Adorno

A squirrel sits amongst leaves in Hyde Park during autumnal weather in London, Britain, November 23, 2019. REUTERS/Henry Nicholls

The U.S. Capitol building is pictured at sunset on Capitol Hill in Washington, U.S., November 22, 2019. REUTERS/Loren Elliott

Ethiopians fish on the Awasa lake in Hawassa, Ethiopia, November 22, 2019. REUTERS/Tiksa Negeri

A great tit sits on a tree on the outskirts of Minsk, Belarus November 22, 2019. REUTERS/Vasily Fedosenko

A woodpecker feeds on a tree on the outskirts of Minsk, Belarus November 22, 2019. REUTERS/Vasily Fedosenko

A rainbow appears in the sky after a rainstorm in Encinitas, California, U.S., November 21, 2019.REUTERS/Mike Blake

The skyline of Beirut is seen during sunset from Antelias, Lebanon November 20, 2019. REUTERS/Andres Martinez Casares

The skyline of Beirut is seen during sunset from Antelias, Lebanon November 20, 2019. REUTERS/Andres Martinez Casares

Autumn colours are seen on foliage during foggy autumn day in Minsk, Belarus November 19, 2019. REUTERS/Vasily Fedosenko

A fisherman digs for bait in front of the Liverpool skyline on the beach at New Brighton, Britain November 19, 2019. REUTERS/Phil Noble

Trees are reflected in a pond in a park in Gaasbeek, Belgium, November 16, 2019. REUTERS/Yves Herman

A view shows the dome of the U.S. Capitol building during sunset in Washington, U.S., November 15, 2019. REUTERS/Yara Nardi

A view shows the U.S. Capitol building during sunset in Washington, U.S., November 15, 2019. REUTERS/Yara Nardi

A view shows the dome of the U.S. Capitol building during sunset in Washington, U.S., November 15, 2019. REUTERS/Yara Nardi

Ducks swim in the reflecting pool between the Lincoln Memorial and the Washington Monument in Washington, U.S., November 14, 2019. REUTERS/Yara Nardi

Creeping desert sands surround the Royal Cemeteries of Meroe Pyramids in Begrawiya at River Nile State, Sudan November 10, 2019. Picture taken November 10, 2019. REUTERS/Mohamed Nureldin Abdallah

Creeping desert sands surround the Royal Cemeteries of Meroe Pyramids in Begrawiya at River Nile State, Sudan November 10, 2019. Picture taken November 10, 2019. REUTERS/Mohamed Nureldin Abdallah

Creeping desert sands surround the Royal Cemeteries of Meroe Pyramids in Begrawiya at River Nile State, Sudan November 10, 2019. Picture taken November 10, 2019. REUTERS/Mohamed Nureldin Abdallah

Tourists walks to the Royal Cemeteries of Meroe Pyramids in Begrawiya at River Nile State, Sudan November 10, 2019. Picture taken November 10, 2019. REUTERS/Mohamed Nureldin Abdallah

Creeping desert sands surround the Royal Cemeteries of Meroe Pyramids in Begrawiya at River Nile State, Sudan November 10, 2019. Picture taken November 10, 2019. REUTERS/Mohamed Nureldin Abdallah

A squirrel sits in a tree in Holland Park during autumnal weather in London, Britain, November 14, 2019. REUTERS/Henry Nicholls

Creeping desert sands surround the Royal Cemeteries of Meroe Pyramids in Begrawiya at River Nile State, Sudan November 10, 2019. Picture taken November 10, 2019. REUTERS/Mohamed Nureldin Abdallah

Cars move through snow covered fields, on a road leading in Oberwarngau, near Munich, Germany November 14, 2019. REUTERS/Andreas Gebert

The sun shines through autumnal leaves at Tiergarten park in Berlin, Germany, November 14, 2019. REUTERS/Fabrizio Bensch

A duck is pictured at Tiergarten park in Berlin, Germany, November 14, 2019. REUTERS/Fabrizio Bensch

A duck swims at Tiergarten park in Berlin, Germany, November 14, 2019. REUTERS/Fabrizio Bensch

Autumnal leaves are pictured at Tiergarten park in Berlin, Germany, November 14, 2019. REUTERS/Fabrizio Bensch

Snow drifts are seen on a summit near the village of Seefeld, Austria, November 14, 2019 REUTERS/Angelika Warmuth

Larches stand in the snow near the village of Seefeld, Austria, November 14, 2019 REUTERS/Angelika Warmuth

Larches stand in the snow near the village of Seefeld, Austria, November 14, 2019 REUTERS/Angelika Warmuth

Larches stand in the snow near the village of Seefeld, Austria, November 14, 2019 REUTERS/Angelika Warmuth

Snow lies on a deck chair in a garden near the village of Seefeld, Austria, November 14, 2019 REUTERS/Angelika Warmuth

The road along the Russian - Norway border is seen in Pasvik valley, Finnmark county, Norway, October 23, 2019. REUTERS/Maxim Shemetov

A seagull flies over a lake on a sunny autumn day in Tervuren, near Brussels, Belgium November 12, 2019. REUTERS/Francois Lenoir

Deer lock antlers as they clash during the rutting season in Richmond Park, west London, Britain, November 12, 2019. REUTERS/Toby Melville TPX IMAGES OF THE DAY

A fisherman is seen during a rainy day at the Rodrigo de Freitas lagoon in Rio de Janeiro, Brazil November 11, 2019. REUTERS/Sergio Moraes

A fisherman is seen during a rainy day at the Rodrigo de Freitas lagoon in Rio de Janeiro, Brazil November 11, 2019. REUTERS/Sergio Moraes

The wreck of the Golden Harvest, a fishing vessel that ran aground on the banks of Loch Linnhe in 2011, is seen in front of the UK's highest mountain Ben Nevis near Fort William, Scotland, Britain November 10, 2019. REUTERS/Russell Cheyne