This aerial photo taken on December 28, 2018 shows commercial and residential buildings in Hong Kong. (Photo by Dale De La Rey/AFP Photo)

People on inflatable boats enjoy the weather on the Lake Lucerne in Sisikon, Switzerland, August 5, 2018. (Photo by Denis Balibouse/Reuters)

Aerial dancers from Voloa, perform a dress rehearsal ahead of their performance at the opening night of Salisbury International Arts Festival on May 20, 2011 in Salisbury, England. The 39th Salisbury International Arts Festival runs from tonight until Saturday 4 June 2011 and features a programme of theatre, dance, circus, film, music, comedy and spoken word in locations around the historic city, from Salisbury Cathedral to Stonehenge. (Photo by Matt Cardy/Getty Images)