The Luis I Bridge was constructed in 1881 to replace an older bridge but was not finished until 1886.
The bridge was initially named Dom Luis I Bridge, after then King Luis I, but the king never showed up during the inauguration in 1886. This made the locals drop the local honorific term, “Dom”, which was given as as sign of respect to nobilities.
Why the king never showed up remains unknown but he was generally despised as the country’s leader as he often ignored many of his royal duties.