Visitors observe the Raphael Rooms at the Vatican Museums, on Feb. 5, 2021. The Vatican Museums, previously closed due to the COVID-19 outbreak, reopened as of Feb. 1, while visitors are required to make appointments on-line before arrival. (Xinhua/Cheng Tingting)

A man wearing a face mask visits the Vatican Museums, on Feb. 5, 2021. The Vatican Museums, previously closed due to the COVID-19 outbreak, reopened as of Feb. 1, while visitors are required to make appointments on-line before arrival. (Xinhua/Cheng Tingting)

Visitors wearing face masks walk in the Vatican Museums, on Feb. 5, 2021. The Vatican Museums, previously closed due to the COVID-19 outbreak, reopened as of Feb. 1, while visitors are required to make appointments on-line before arrival. (Xinhua/Cheng Tingting)

People wearing face masks visit the Vatican Museums, on Feb. 5, 2021. The Vatican Museums, previously closed due to the COVID-19 outbreak, reopened as of Feb. 1, while visitors are required to make appointments on-line before arrival. (Xinhua/Cheng Tingting)

People wearing face masks visit the Vatican Museums, on Feb. 5, 2021. The Vatican Museums, previously closed due to the COVID-19 outbreak, reopened as of Feb. 1, while visitors are required to make appointments on-line before arrival. (Xinhua/Cheng Tingting)

A man wearing a face mask visits the Vatican Museums, on Feb. 5, 2021. The Vatican Museums, previously closed due to the COVID-19 outbreak, reopened as of Feb. 1, while visitors are required to make appointments on-line before arrival. (Xinhua/Cheng Tingting)

A visitor wearing a face mask walks down the staircase of Vatican Museums, on Feb. 5, 2021. The Vatican Museums, previously closed due to the COVID-19 outbreak, reopened as of Feb. 1, while visitors are required to make appointments on-line before arrival. (Xinhua/Cheng Tingting)

A man wearing a face mask visits the Vatican Museums, on Feb. 5, 2021. The Vatican Museums, previously closed due to the COVID-19 outbreak, reopened as of Feb. 1, while visitors are required to make appointments on-line before arrival. (Xinhua/Cheng Tingting)

A visitor wearing a face mask looks at the "Laocoön and His Sons" sculpture at the Vatican Museums, on Feb. 5, 2021. The Vatican Museums, previously closed due to the COVID-19 outbreak, reopened as of Feb. 1, while visitors are required to make appointments on-line before arrival. (Xinhua/Cheng Tingting)

A man wearing a face mask listens to the audio guide as he vists the Raphael Rooms at the Vatican Museums, on Feb. 5, 2021. The Vatican Museums, previously closed due to the COVID-19 outbreak, reopened as of Feb. 1, while visitors are required to make appointments on-line before arrival. (Xinhua/Cheng Tingting)

People wearing face masks visit the Vatican Museums, on Feb. 5, 2021. The Vatican Museums, previously closed due to the COVID-19 outbreak, reopened as of Feb. 1, while visitors are required to make appointments on-line before arrival. (Xinhua/Cheng Tingting)

People wearing face masks visit the Vatican Museums, on Feb. 5, 2021. The Vatican Museums, previously closed due to the COVID-19 outbreak, reopened as of Feb. 1, while visitors are required to make appointments on-line before arrival. (Xinhua/Cheng Tingting)