It is the only Roman wall in the world that has been preserved almost in its entirety. It was built between the end of the 3rd century and the beginning of the 4th century, following the canons laid down by Vitruvius. It is more than two kilometres long and preserves seventy-one of the eighty-five original towers. The wall has ten gates, five of which existed in Roman times, although they have been modified. It has an average height of ten metres and at some points, it can reach a width of seven metres.

The ancient Lucus Augusti treasures exceptional monuments within its walls, such as the cathedral of Santa María, a large Romanesque church that has the privilege of permanently exhibiting the Blessed Sacrament.

The city walls were declared a National Historic Monument in 1921 to give them greater protection, and Lugo’s city centre was recognised as a Historic Site in 1973. In 2000, UNESCO declared the Roman wall of Lugo a World Heritage Site.