1) Belgrade, Serbia
2) Budapest, Hungary
3) Zagreb, Croatia
4) Ljubljana, Slovenia
Explanation:
On November 22, 2019, World Athletics Council declared Belgrade, Serbia to host its first-ever World Athletics Indoor Championships 2022 and Yangzhou, China was confirmed as the host city of the World Athletics Half Marathon Championships 2022.Belgrade as host- Belgrade has hosted many track and field events over the years such as 1962 European Championships, 2013 European Cross Country Championships, 2017 European Indoor Championships, and the 2017 Balkan Championships.