The loudest cheers were for Danish riders such as Jonas Vingegaard and for the biggest names led by champion Tadej Pogacar.
Staff at the park said only rock stars had attracted such crowds before.
Pogacar, who rides for UAE Team Emirates’, said he was excited too.
“As a team we are ready, and me and as an individual I’m ready too, so I can’t wait to start of Friday with the time trial,” the Slovenian said.
Denmark’s Crown Prince Frederik attended the official unveiling of the teams, two days before the 21-day Tour opens with a 13km time-trial, the first of three stages in Denmark.
Tivoli Park has around 25 fairground rides. On Wednesday the 176 cyclists added one, riding round a special 1km track to be greeted by thousands of smiling, cheering and filming fans.
“I feel great, especially today with all these people in Copenhagen, you can only be happy.” said Pogacar.