The City of London financial district is seen as people sit aboard a sightseeing boat on the River Thames, amid the coronavirus disease (COVID-19) pandemic in London, Britain, July 27, 2021. REUTERS/Henry Nicholls

British tourists wearing protective face masks walk with their luggage, as they arrive at Malaga-Costa del Sol Airport for sightseeing, amid the coronavirus disease (COVID-19) outbreak in Malaga, Spain, July 19, 2021. REUTERS/Jon Nazca

A British tourist, who is fully vaccinated against the coronavirus disease (COVID-19), wears a protective face mask, as she walks with his luggage after arriving at Malaga-Costa del Sol Airport for sightseeing, amid the coronavirus disease (COVID-19) outbreak in Malaga, Spain, July 19, 2021. REUTERS/Jon Nazca

Students at Michigan?s Clarkston Junior High School get a temperature check by school principal Adam Kern outside their hotel before boarding a tour bus to go sightseeing in Washington, in Sterling, Virginia, U.S., June 18, 2021. Picture taken June 18, 2021. REUTERS/Evelyn Hockstein

Daniel Bradstreet, a student at Michigan?s Clarkston Junior High School, has his temperature checked by school principal Adam Kern outside their hotel before boarding a tour bus with his classmates to go sightseeing in Washington, in Sterling, Virginia, U.S., June 18, 2021. Picture taken June 18, 2021. REUTERS/Evelyn Hockstein

German tourists disembark for sightseeing from the cruise ship 'Mein Schiff 2' of the company TUI Cruises after it was docked at dawn in Malaga port, becoming the first cruise ship carrying tourists to arrive on Spain's mainland since June 2020, amid the coronavirus disease (COVID-19) pandemic, in Malaga, southern Spain, June 15, 2021. REUTERS/Jon Nazca

German tourists disembark for sightseeing from the cruise ship 'Mein Schiff 2' of the company TUI Cruises after it was docked at dawn in Malaga port, becoming the first cruise ship carrying tourists to arrive on Spain's mainland since June 2020, amid the coronavirus disease (COVID-19) pandemic, in Malaga, southern Spain, June 15, 2021. REUTERS/Jon Nazca

German tourists disembark for sightseeing from the cruise ship 'Mein Schiff 2' of the company TUI Cruises after it was docked at dawn in Malaga port, becoming the first cruise ship carrying tourists to arrive on Spain's mainland since June 2020, amid the coronavirus disease (COVID-19) pandemic, in Malaga, southern Spain, June 15, 2021. REUTERS/Jon Nazca

German tourists watch members of singing groups of Verdiales, known as "pandas", as they disembark for sightseeing from the cruise ship 'Mein Schiff 2' of the company TUI Cruises after it was docked at dawn in Malaga port, becoming the first cruise ship carrying tourists to arrive on Spain's mainland since June 2020, amid the coronavirus disease (COVID-19) pandemic, in Malaga, southern Spain, June 15, 2021. REUTERS/Jon Nazca

People ride on a sightseeing boat down the River Thames during sunny weather, amid the coronavirus disease (COVID-19) outbreak, in London, Britain, June 5, 2021. REUTERS/Henry Nicholls

A sightseeing boat with empty seats is pictured on the Spree river, amid the coronavirus disease (COVID-19) pandemic, in Berlin, Germany May 30, 2021. REUTERS/Annegret Hilse

A child wearing a face mask poses for a picture as passengers enjoy an open-top sightseeing bus tour, operated by Hato Bus Co., as the tour service resumed after Japan's government lifted the coronavirus disease (COVID-19) state of emergency in the Tokyo area, in Tokyo, Japan March 22, 2021. REUTERS/Androniki Christodoulou

A tour guide of Hato Bus Co. disinfects seats of an open-top sightseeing bus, as the tour service resumed after Japan's government lifted the coronavirus disease (COVID-19) state of emergency in the Tokyo area, in Tokyo, Japan March 22, 2021. REUTERS/Androniki Christodoulou

Passengers wearing protective face masks enjoy viewing blooming cherry blossoms from an open-top sightseeing bus, operated by Hato Bus Co., after Japan's government lifted the coronavirus disease (COVID-19) state of emergency in the Tokyo area, in Tokyo, Japan March 22, 2021. REUTERS/Androniki Christodoulou

Passengers wearing protective face masks enjoy the viewing of Tokyo Station building from an open-top sightseeing bus, operated by Hato Bus Co., after Japan's government lifted the coronavirus disease (COVID-19) state of emergency in the Tokyo area, in Tokyo, Japan March 22, 2021. REUTERS/Androniki Christodoulou

Passengers wearing protective face masks enjoy viewing blooming cherry blossoms from an open-top sightseeing bus, operated by Hato Bus Co., after Japan's government lifted the coronavirus disease (COVID-19) state of emergency in the Tokyo area, in Tokyo, Japan March 22, 2021. REUTERS/Androniki Christodoulou

A tour guide of Hato Bus Co. works at an open-top sightseeing bus as the tour service resumed after Japan's government lifted the coronavirus disease (COVID-19) state of emergency in the Tokyo area, in Tokyo, Japan March 22, 2021. REUTERS/Androniki Christodoulou

A flight attendant wearing an Xpore top designed for safe traveling, walks the catwalk during a sightseeing flight, amid the spread of the coronavirus disease (COVID-19), in Taipei, Taiwan November 19, 2020. REUTERS/Ann Wang TPX IMAGES OF THE DAY

Flight attendants wear Xpore made tops designed for safe traveling amid the spread of the coronavirus disease (COVID-19), during a sightseeing flight in Taipei, Taiwan November 19, 2020. REUTERS/Ann Wang

Flight attendants wear Xpore made tops designed for safe traveling amid the spread of the coronavirus disease (COVID-19), during a sightseeing flight in Taipei, Taiwan November 19, 2020. REUTERS/Ann Wang

Passengers take a selfie while wearing protective outfit before boarding a sightseeing flight, amid the spread of the coronavirus disease (COVID-19), in Taipei, Taiwan November 19, 2020. REUTERS/Ann Wang

People wearing protective outfits prepare to board a sightseeing flight, amid the spread of the coronavirus disease (COVID-19), in Taipei, Taiwan November 19, 2020. REUTERS/Ann Wang

A flight attendant serves food to passengers during a sightseeing flight, amid the spread of the coronavirus disease (COVID-19), in Taipei, Taiwan November 19, 2020. REUTERS/Ann Wang

A monitor shows the route of a sightseeing flight, during the global outbreak of the coronavirus disease (COVID-19), in Taipei, Taiwan November 19, 2020. REUTERS/Ann Wang

A woman wearing a protective face mask takes pictures at a sightseeing spot, with the Moscow International Business Centre seen in the background, in Moscow, Russia November 6, 2020. REUTERS/Evgenia Novozhenina

A woman holds an umbrella while walking along a sightseeing spot in Moscow, Russia November 6, 2020. REUTERS/Evgenia Novozhenina

Visitors wearing protective face masks practice social distancing as they offer prayers at a temple at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan October 13, 2020. REUTERS/Issei Kato

A sign for 'Go To Travel' campaign, a Japanese government-backed travel discount program encouraging domestic travel to help boost the economy, is displayed at a traditional rice crackers store along Nakamise Street at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan October 13, 2020. REUTERS/Issei Kato

A sign for 'Go To Travel' campaign, a Japanese government-backed travel discount program encouraging domestic travel to help boost the economy, is displayed at a souvenir shop along Nakamise Street at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan October 13, 2020. REUTERS/Issei Kato

Visitors wearing protective face masks are seen at a temple at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan October 13, 2020. REUTERS/Issei Kato

Visitors wearing protective face masks are seen at a temple at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan October 13, 2020. REUTERS/Issei Kato

Kimono-clad tourists wearing protective face masks are seen at a temple at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan October 13, 2020. REUTERS/Issei Kato

Kimono-clad tourists wearing protective face masks are seen at a temple at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan October 13, 2020. REUTERS/Issei Kato

Visitors wearing protective face masks walk along Nakamise Street at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan October 13, 2020. REUTERS/Issei Kato

Kimono-clad tourists wearing protective face masks walk along Nakamise Street at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan October 13, 2020. REUTERS/Issei Kato

Kimono-clad tourists wearing protective face masks walk along Nakamise Street at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan October 13, 2020. REUTERS/Issei Kato

A sightseeing bus passes Oxford University building, amid the spread of the coronavirus disease (COVID-19), in Oxford, Britain, October 6, 2020. REUTERS/Matthew Childs

People sit on a sightseeing boat on the River Thames, amid the coronavirus disease (COVID-19) outbreak, in London, Britain, August 21, 2020. REUTERS/Henry Nicholls

Passersby wearing protective face masks are seen at Takeshita Street, a popular sightseeing spot amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan July 29, 2020. REUTERS/Issei Kato

A woman in yukata, or casual summer kimono, poses for a photo at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan July 22, 2020. REUTERS/Issei Kato

Mannequins in Japanese traditional costumes and wearing protective face masks are displayed at a souvenir shop at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan July 22, 2020. REUTERS/Issei Kato

Visitors wearing protective face masks walk along Nakamise Street at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan July 22, 2020. REUTERS/Issei Kato

An elderly woman wearing a protective face mask walks at a Buddhist temple at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan July 22, 2020. REUTERS/Issei Kato

Women in yukata, or casual summer kimonos, wearing protective face masks, walk along Nakamise Street at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan July 22, 2020. REUTERS/Issei Kato

Women in yukata, or casual summer kimonos, wearing protective face masks, walk along Nakamise Street at Asakusa district, a popular sightseeing spot, amid the coronavirus disease (COVID-19) outbreak in Tokyo, Japan July 22, 2020. REUTERS/Issei Kato

Passengers Pia Rusp and Michael Rusp from Germany walk during a sightseeing following the coronavirus disease (COVID-19) outbreak in Budapest, Hungary, July 17, 2020. Picture taken July 17, 2020. REUTERS/Bernadett Szabo REFILE - CORRECTING NAMES

People take part in a campaign by Israel's Nature and Parks Authority calling on Israelis to join sightseeing tours and find comfort in tree hugging amid a spike in the coronavirus disease (COVID-19), in Apollonia National Park, near Herzliya, Israel July 7, 2020. Picture taken July 7, 2020. REUTERS/Ronen Zvulun TPX IMAGES OF THE DAY

A woman takes part in a campaign by Israel's Nature and Parks Authority calling on people to join sightseeing tours and find comfort in tree hugging amid a spike in the coronavirus disease (COVID-19), in Jerusalem July 9, 2020. Picture taken July 9, 2020. REUTERS/Ronen Zvulun

A couple take part in a campaign by Israel's Nature and Parks Authority calling on Israelis to join sightseeing tours and find comfort in tree hugging amid a spike in the coronavirus disease (COVID-19), as part of Jerusalem's Old City walls are seen in the background July 9, 2020. Picture taken July 9, 2020. REUTERS/Ronen Zvulun

A couple take part in a campaign by Israel's Nature and Parks Authority calling on Israelis to join sightseeing tours and find comfort in tree hugging amid a spike in the coronavirus disease (COVID-19), in Apollonia National Park, near Herzliya, Israel July 7, 2020. Picture taken July 7, 2020. REUTERS/Ronen Zvulun

People take part in a campaign by Israel's Nature and Parks Authority calling on Israelis to join sightseeing tours and find comfort in tree hugging amid a spike in the coronavirus disease (COVID-19), in Apollonia National Park, near Herzliya, Israel July 7, 2020. Picture taken July 7, 2020. REUTERS/Ronen Zvulun

A tour guide adjust her face mask to protect herself from the coronavirus disease (COVID-19) in an empty Taipei Sightseeing bus in Taipei, Taiwan, May 22, 2020. REUTERS/Ann Wang

A tour guide speaks to a microphone while wearing a face mask to protect herself from the coronavirus disease (COVID-19) in an empty Taipei Sightseeing bus in Taipei, Taiwan, May 22, 2020. REUTERS/Ann Wang

A staff member collects equipments after disinfecting a Taipei Sightseeing bus before the bus head out on the designated route to various tourist sites across the city in Taipei, Taiwan, May 22, 2020. REUTERS/Ann Wang

A staff wears a full body protective suit while disinfecting a Taipei Sightseeing bus before the bus head out on the designated route to various tourist sites across the city in Taipei, Taiwan, May 22, 2020. REUTERS/Ann Wang

A staff takes off a full body protective suit after disinfecting a Taipei Sightseeing bus before the bus head out on the designated route to various tourist sites across the city in Taipei, Taiwan, May 22, 2020. REUTERS/Ann Wang

A passerby walks between temporally closed shops at almost empty Nakamise Street as the spread of the coronavirus disease (COVID-19) continues, at Asakusa district, a popular sightseeing spot, in Tokyo, Japan May 21, 2020. REUTERS/Issei Kato

A passerby wearing a protective face masks walks between temporally closed shops along Nakamise Street as the spread of the coronavirus disease (COVID-19) continues, at Asakusa district, a popular sightseeing spot, in Tokyo, Japan May 21, 2020. REUTERS/Issei Kato

Passersby wearing protective face masks walk between temporally closed shops along Nakamise Street as the spread of the coronavirus disease (COVID-19) continues, at Asakusa district, a popular sightseeing spot, in Tokyo, Japan May 21, 2020. REUTERS/Issei Kato TPX IMAGES OF THE DAY

People gather at a sightseeing point amid the coronavirus disease (COVID-19) outbreak in Moscow, Russia May 5, 2020. REUTERS/Maxim Shemetov