Summer Olympic Games demand for tickets to all levels of each event, there was controversy when seats set aside for sponsors and National Delegations went unused in the early days. A system of reallocation was put in place so the empty seats were filled throughout the Games. Rio de Janeiro, Brazil hosted the 2016 Summer Olympics, becoming the third city in the Southern Hemisphere to host the Olympic Games after Melbourne, Australia, in 1956 and Sydney, Australia, in 2000, and the first South American city to host the Olympics. The preparation for these Games was overshadowed by controversies, including the instability of Brazil's
Winter Olympic Games the qualifying host countries are limited to those that have the resources and infrastructure to successfully host an Olympic Games without negatively impacting the region or nation; this consequently rules out a large portion of the developing world. Finally, any prospective host city planning to bid for the Games is required to add a "legacy plan" to their proposal, with a view to the long-term economic and environmental impact that hosting the Olympics will have on the region. For the 2022 Winter Games, IOC allowed a longer distance between the alpine events and other events. The Oslo bid had to