UNESCO is deciding whether to put the Brazilian capital on its list of World Heritage sites in danger.
A team of experts arrived in Brasilia Tuesday for a four-day mission.
They'll evaluate whether damage to the city's unique futuristic architecture and changes to its initial design mean it needs to be on the endangered list.
Brasilia was inaugurated in 1960, complete with iconic buildings designed by famed architect Oscar Niemeyer. The city was named a World Heritage site by the United Nations Educational, Scientific and Cultural Organization in 1987.
Inclusion on the Paris-based organization's in-danger list means the site must comply with UNESCO's conservation recommendations to retain its designation.