Atltico Madrid's players and coaching staff started the festivities on an open-top bus with ``League Champions'' written on the side, slowly making their way from Vicente Calderon Stadium to the city's Neptune fountain, the club's traditional site for celebrating trophies.
Atltico Madrid won its first league title since 1996 on Saturday when it drew 1-1 at title rival FC Barcelona.
It can add the Champions League title to round off its already spectacular season when it plays crosstown rival Real Madrid in Saturday's final in Lisbon.
Supporters lined the streets waving scarves and flags with the club's red-and-white colors, and many more waited around a stage where the team was introduced individually to cheers from the crowd.
It's an honor to be here with the guys I share the locker room with, they have given it their all,'' said team captain Gabi Fernandez. ``This has just begun and the best is yet to come.''
The largest applause were for coach Diego Simeone, who played for Atletico the last time it won the league. The sea of supporters greeted the Argentine manager with ``Ole! Ole! Ole! Cholo Simeone!''
``This is not only about the league,'' Simeone said. ``The most important thing that this group has shown is that if you work hard and want it enough you can do it.''
With a squad that cost a fraction of what FC Barcelona and Real Madrid invested in their star-studded teams, Atltico Madrid was able to break the two powerhouses' hold on the league title for the first time since Valencia won it in 2004.