GENEVA — In an era of radically rethinking how and where to play international soccer, the European Championship has helped make constant change the norm.
Euro 2020 will start on June 11 with 24 teams playing game around the continent, from Glasgow to Munich to St. Petersburg. It's an idea no less stunning now than nine years ago when it was floated by European soccer's then-president, Michel Platini.
It follows Euro 2016, which debuted a 24-team lineup instead of the usual 16-team format that many argued was the best balanced and most competitive setup.
UEFA has at least retained four-team groups, which have been the core of men's national team tournaments since the 1958 World Cup.
Those will disappear from FIFA's expanding World Cup after the 2022 edition in Qatar. The 2026 World Cup in North America will have 16 groups of three teams each playing only two games before a last-32 knockout bracket.
Amid the continuous changes, Euro 2024 looms as a traditional tournament low on risk and high on familiarity for players, fans and UEFA.
Germany will host it alone in established stadiums, with nine of the 10 also used at the 2006 World Cup. That event was popular with fans who could rely on free trains instead of airplanes.
How will Euro 2028 look when UEFA next has the option to experiment?
UEFA president Aleksander Ceferin has said multi-nation hosting is only for Euro 2020, which he inherited from Platini.
In a statement, UEFA said it will publish Euro 2028 bidding details and a timeline later this year. Hosting decisions are typically taken by the executive committee six years ahead of the tournament.
UEFA could be spoiled for choice in the next 18 months.
Among strong potential candidates who can host alone without major spending on stadiums and airports are Russia and either of England or Spain, depending on which is not selected by UEFA as Europe's candidate for the 2030 World Cup.
Italy and Turkey, which once seemed sure to host Euro 2020, might see 2028 bidding as a catalyst for stadium upgrades.
Politics rather than soccer issues was also a key reason for changes under Platini.
Expansion to 24 teams was agreed to in 2008 and was tied to election promises that helped him win the previous year.
Adding eight more teams also created 20 more games and one more knockout round at Euro 2016, raising revenues by 40% to 1.93 billion euros ($2.35 billion). UEFA used that money to fund member federations' four-year grants worth double what FIFA pays them.
UEFA also picked the pan-continent Euro 2020 option after being left with a weak field of bidders. Turkey was openly supported by Platini until its government focused on Istanbul's doomed bid to host the 2020 Olympics.
Amid the uncertainty in an economic downturn, Platini announced the multi-nation Euro 2020 plan — in Kyiv ahead of the Euro 2012 final — to help save future hosts from the costs Ukraine paid.
"If we look at the investments made in stadiums for just three games, it is very expensive," Platini said in 2012, after previously expressing sympathy with Ukrainian cities Kharkiv and Lviv.
Qatar is preparing to show a 32-team tournament can be hosted in only eight stadiums, though sporting and commercial reasons count against a future European Championship featuring 32 of UEFA's 55 member countries.
Even with 24 teams at Euro 2020, one of the six groups is stacked with defending champion Portugal and the past two World Cup winners, France and Germany.
A 32-team European Championship would dilute the group stage and devalue UEFA-managed broadcast rights for a qualifying program which already lacks drama.
After costs for postponing Euro 2020 ran to tens of millions of euros (dollars), UEFA can expect a stable and profitable Euro 2024 to help the soccer industry face its own "long COVID" issues.
A similar kind of tournament would be a safe bet for 2028.