CHICAGO — The Chicago Stair climb returned to the city for its 15th year Sunday morning where thousands of people climb 105 floors of the Willis Tower.

The Shirley Ryan AbilityLab is a non-profit organization that raises funds to help advance human ability. People from all backgrounds and abilities came together to support the cause.

Nearly 2,000 people participated in this year’s event.

The Ability Lab is hoping to raise one million dollars to help their cause and empower the community.

It’s the 15th year of the Chicago Skyrise also marking the 50th birthday of the Willis Tower.