A home victory on the final day of the Serie B season has helped Bologna to clinch a return to Italy's top flight after a three-year absence.
Massimo Marazzina's ninth minute penalty was enough to beat Pisa 1-0 to secure the runners-up spot in Serie B and the all-important promotion.
In a close run contest, the seven-times Italian champions held off the challenge of Lecce, who also won 1-0 against Vicenza to finish a point behind in third.
It means Lecce must now play-off with Albinoleffe, Brescia and Pisa for the final promotion berth.
"We have worked with enthusiasm over the last three years and that has allowed us to recover as a club to the point where 35,000 people turned up today," Bologna President Alfredo Cazzola said.
"This club and this city definitely deserve a place in Serie A. We asked the fans not to invade the pitch so that the squad could do a lap of honour and they did.
"I am very proud that we have completed the mission we set for ourselves two and a half years ago."
Bologna's promotion comes as it was recently revealed that the club are the subject of takeover interest from an American consortium.
Chievo, who won promtion to Serie A last week, secured the championship with a 2-2 draw at home to Bari.
Lecce travel to Pisa on Wednesday in the first leg of the play-off semi-finals, with the return game next Sunday. In the other semi-final, Albinoleffe host Brescia in the first leg.
The two winners will play in the final on June 11 and June 15 for the last spot in Serie A.
[WEEK 42 REVIEW]