Gamle Bybro, also known as Bybroa or Lykkens Portal, is a historic bridge in Trondheim, built in 1681 by Johan Caspar von Cicignon after the Great Fire of the city. The bridge crosses the Nidelva River and connects Kjøpmannsgata with Bakklandet. Originally constructed of wood, it is supported by three stone pillars and has undergone several changes since its opening.
The bridge has military strategic importance and is closely associated with Kristiansten Fortress. It is known for its characteristic red gates and offers beautiful views of the river as well as the charming, colorful houses that line the banks. Gamle Bybro is an important landmark in Trondheim and a popular place for both locals and visitors.