Manchester City, who played Gillingham in the Second Division (now League One) play-off final in 1999, are now preparing to face Chelsea in the Champions League final.
Here, the PA news agency looks at some of the key dates in the club's journey from the English third tier to the top of the European game.
1999: Promoted to First Division (second tier) after beating Gillingham on penalties in Second Division play-off final.
2000: Promoted to Premier League; Phil Foden born.
2001: Relegated to First Division.
2002: Promoted to Premier League.
2003: Left Maine Road for City of Manchester (now Etihad) Stadium.
2007: Club taken over by former Thai prime minister Thaksin Shinawatra.
2008: Club sold by Shinawatra to the Abu Dhabi United Group, the investment vehicle of Sheikh Mansour; Robinho signed for British record £32.5million among flurry of big-money deals; Vincent Kompany also joined club.
2009: Carlos Tevez headlined a summer of star signings as he quit Manchester United for City.
2010: Fifth in Premier League; City sign David Silva and Yaya Toure.
2011: Club finish third in Premier League, qualify for Champions League for first time and win FA Cup, their first trophy for 35 years; sign Sergio Aguero.
2012: Win first Premier League title.
2014: Win Premier League and League Cup.
2015: Sign Kevin De Bruyne and Raheem Sterling.
2016: Win League Cup and reach Champions League semi-finals; Pep Guardiola appointed manager.
2018: Win Premier League with record 100 points and League Cup.
2019: Win domestic treble.
2020: Win League Cup; overturn two-year ban from European competition for Financial Fair Play breaches following appeal to Court of Arbitration for Sport; sign Ruben Dias for club record £64.3million.
2021: Win Premier League and League Cup and reach Champions League final for first time.