Belgian Prime Minister Sophie Wilmes attends a ceremony to reopen the Atomium in Brussels, Belgium, June 1, 2020. The Atomium reopened to the public on Monday. The landmark was previously closed due to the impact of the COVID-19 pandemic. (Xinhua/Zheng Huansong)

Belgian Prime Minister Sophie Wilmes (C) attends a ceremony to reopen the Atomium in Brussels, Belgium, June 1, 2020. The Atomium reopened to the public on Monday. The landmark was previously closed due to the impact of the COVID-19 pandemic. (Xinhua/Zheng Huansong)

Tourists wait to visit the Atomium in Brussels, Belgium, June 1, 2020. The Atomium reopened to the public on Monday. The landmark was previously closed due to the impact of the COVID-19 pandemic. (Xinhua/Zheng Huansong)

Belgian Prime Minister Sophie Wilmes (L) attends a ceremony to reopen the Atomium in Brussels, Belgium, June 1, 2020. The Atomium reopened to the public on Monday. The landmark was previously closed due to the impact of the COVID-19 pandemic. (Xinhua/Zheng Huansong)

Photo taken on June 1, 2020 shows the Atomium in Brussels, Belgium. The Atomium reopened to the public on Monday. The landmark was previously closed due to the impact of the COVID-19 pandemic. (Xinhua/Zheng Huansong)

Staff members of the Atomium wait for the arrival of tourists in Brussels, Belgium, June 1, 2020. The Atomium reopened to the public on Monday. The landmark was previously closed due to the impact of the COVID-19 pandemic. (Xinhua/Zheng Huansong)

Belgium's Princess Astrid cuts the ribbon during a ceremony to reopen the Atomium in Brussels, Belgium, June 1, 2020. The Atomium reopened to the public on Monday. The landmark was previously closed due to the impact of the COVID-19 pandemic. (Xinhua/Zheng Huansong)

A staff member of the Atomium waits for the arrival of tourists in Brussels, Belgium, June 1, 2020. The Atomium reopened to the public on Monday. The landmark was previously closed due to the impact of the COVID-19 pandemic. (Xinhua/Zheng Huansong)

Photo taken on June 1, 2020 shows the Atomium in Brussels, Belgium. The Atomium reopened to the public on Monday. The landmark was previously closed due to the impact of the COVID-19 pandemic. (Xinhua/Zheng Huansong)