Millennium Park transformed a former railroad and parking corridor on the northwestern edge of Grant Park into a major civic and cultural space in downtown Chicago. Built over garages, commuter rail lines, and Millennium Station after the city acquired air rights in 1997, it opened in 2004 after delays and large cost overruns but won broad praise for its design and impact. Its prominent features include Frank Gehry’s Jay Pritzker Pavilion and BP Pedestrian Bridge, along with Cloud Gate, Crown Fountain, and Lurie Garden. Widely recognized for accessibility and green design, the park helped reshape nearby downtown development and became Chicago’s most visited tourist destination.