International Olympic Committee President Thomas Bach said that Barcelona was a city "living with its back turned" before the 1992 Summer Games, which opened 25 years ago today.
The German gave a speech in the Spanish city to mark the anniversary of an Olympic Games which are widely credited with transforming the Catalan capital.
He was present at the Centre d’Alt Rendiment Esportiu - a high performance sports centre itself celebrating 30 years since formation.
Spanish monarch Felipe VI was among others to attend the celebrations.
In 1992, the King, then the heir to the throne, was a member of the Spanish sailing team and was chosen as the host nation's flagbearer for the Opening Ceremony at the Montjuic Stadium.
"Sport has the unique power to unite all people," said Bach.
"The magic of the Olympic Games brought the world to Barcelona - and the Olympic Games brought a new Barcelona to the world.
"The Olympic Games transformed Barcelona.
"Until the Olympic Games, Barcelona was living with its back turned to the beautiful Mediterranean.
"The Olympic Games allowed Barcelona to turn around and truly embrace the sea.
"It also brought many other improvements that the citizens of Barcelona still enjoy today."
Improvements in Barcelona included an upgrade to the famous La Rambla boulevard and, notably, a significant improvement to the waterfront.
Two miles of beach were installed with the city now one of the most popular tourist destinations in Europe.
Commerce was also boosted with one annual report moving Barcelona up from 11th to fourth in the European rankings for best cities to do business in.
The number of hotel rooms in the city more than doubled between 1990 and 2004.
A visual show looked back on the Barcelona 1992 Games today, where hosts Spain won 22 medals, including 13 golds.
That was enough to finish sixth on the medals table, with the Centre d’Alt Rendiment Esportiu credited for much of this success.
"Just like the Olympic Games were a turning point for Barcelona, this Centre represents a turning point for Spanish sport," said Bach.
"This Centre is the foundation for the great sporting achievements of so many Spanish Olympians.
"This state-of-the-art centre was the foundation for Spain’s best-ever Olympic performance in 1992.
"It continues to produce Olympic champions to this day.
"Barcelona and Spain can be very proud of this sporting legacy."
The Olympic Channel has marked the anniversary, including full event replays of iconic moments.
This includes archer Antonio Rebollo's flaming arrow which lit the Olympic flame during the Opening Ceremony.
Diving - which provided some of the most memorable images when competitors performed against the Barcelona skyline - has also been featured.
Fu Mingxia of China won the gold medal during the women's 10-metre platform final at the age of just 13.
Other notable incidents include Britain's 400 metres runner Derek Redmond, who was supported to the finish line by his father Jim after an injury left him in tears.
Ethiopia's Derartu Tulu and Elana Meyer of South Africa joined hands for a victory lap after the women's 10,000m final, after finishing in first and second respectively.
The United States "dream team" men's basketball side cruised to gold medal while hosts Spain won in the men's football.