Nation days at EXPOs are days on which the individual countries present themselves to the public and the host (country) at a world exhibition.
The main program items of a Nation's Day include a flag ceremony and an event hosted by the corresponding (host) country.
Nation Days are often held at World's Fairs on the actual national holidays of the countries.
Some countries that do not have "official" national holidays are given a "day of honor" (e.g., at EXPO 2020 in Dubai).
This also applies to countries whose national holiday does not fall within the six-month EXPO period. (E.g. France. Here, the national holiday is July 14. However, the EXPO in Dubai took place between October and March).
During these Nation Days, a country hosts different events on the main stages of the EXPOs and around its own pavilion.
Usually during the day there is a parade with guests of honor, leaders and staff of the pavilion, as well as artists, musicians and dance groups.
Each country can design its Nation Day according to its own ideas under certain conditions.