Image: ©Copyright Japan Association for the 2025 World Exposition
72
Expos listed
On the International Exhibitions Bureau list: 70 held and 2 scheduled
Since 1851
Years of Expos
The first Expo opened May 1, 1851
4
Eras of rules
Pre-Convention, First, Second and Third Systems
01 Definition
What are Expos?
Expos are international mega-events that involve the official participation of national governments, and their main purpose is the education of the public.
Three things set them apart. They are international: the official participants are governments of foreign countries, invited through diplomatic channels. They are mega-events: large in scale, with a long-term effect on the host country. And they are cultural, not commercial: their purpose is to educate.
The definition comes from the Convention Relating to International Exhibitions, signed in Paris on November 22, 1928. Article 1 defines an exhibition as “a display which, whatever its title, has as its principal purpose the education of the public.” It leaves out exhibitions lasting less than three weeks or more than six months, fine arts exhibitions and exhibitions of an essentially commercial nature. Today, 184 countries are bound by the Convention.
The International Exhibitions Bureau (Bureau International des Expositions, BIE) applies the Convention and registers or recognizes each Expo. Expomuseum names every edition the same way, Expo Year City, uses the Convention’s own category names and covers the Expos on the BIE list. Horticultural Expos and the Triennale di Milano are outside Expomuseum’s scope.
02 Start here
Nine ways in
Visit Expo 2027 Belgrade
A visitor guide to Expo 2027 Belgrade, May 15 to August 15, 2027: the site at a glance, ten tips and a checklist.
Timeline
Every Expo in order, from 1851 to the next one. Filter by categorization system or category.
Tips
How to make the most of an Expo: when to go, which lines are worth it and why to talk to pavilion staff.
Categories
The four categorization systems, and why official categories and promotional labels often disagree.
Library
A curated directory of websites, digital archives, online groups and other resources on Expos.
03 Happening next
● Next Expo, opens in 192 days
Expo 2027 Belgrade
May 15 to August 15, 2027
Theme: “Play for Humanity: Sport and Music for All”
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DaysHoursMinutes
Expo 2027 Belgrade, a recognized Expo, runs May 15 to August 15, 2027, under the theme "Play for Humanity: Sport and Music for All." The first Expo in the Western Balkans brings more than 130 countries to a 25-hectare site near the Sava River, where pavilions, stages, and sports courts explore how play builds resilience, drives innovation and connects people.
04 Classification
Four eras of Expos
Before the 1928 Convention, no international standard existed. The Convention created one, in force since 1931, and its categories were redefined twice, by the 1972 Protocol and the 1988 amendment. We call the result the Pre-Convention, First, Second and Third Systems.
●
1851-1933
Pre-Convention
21 Expos
No international standard; each host set its own rules.
●
1935-1975
First System
28 Expos
General exhibitions of the first and second category, and special exhibitions.
●
1981-2005
Second System
14 Expos
Universal and specialized exhibitions, after the 1972 Protocol.
●
2008 onward
Third System
9 Expos
Registered and recognized Expos, after the 1988 amendment.
05 Records
Expos by the numbers
Four records, each computed from the Expos collection and checked against the BIE. The full comparison lives on its own page.
Most visited
73.1M
Expo 2010 Shanghai
73,085,000 visits
Largest site
600 HA
Expo 2030 Riyadh
1,483 acres
Most participating countries
192
Expo 2020 Dubai
countries only; organizations not counted
Longest run
288 DAYS
Expo 1915 San Francisco
first season only for multi-season Expos
06 Keep exploring