The six-month global exhibition runs until October 13 on the artificial island of Yumeshima in Osaka Bay, with some 158 countries and regions taking part.
Organizers expect over 28 million visitors during the event.
Among the standout participants is Poland, which has invested PLN 165 million (EUR 38.5 million, USD 44 million) to promote itself at the event and strengthen trade ties with Japan.
Despite rainy and windy weather, huge crowds gathered outside the Polish pavilion on Sunday for the grand opening.
Photos: Danuta Isler/Polish Radio
Danuta Isler was on the ground and filed this report from day one of the Expo.
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