Two thousand years ago, they helped to protect the town of Horncastle from the very real threat posed by Saxon invaders.
Now, it appears the town’s once mighty Roman walls are facing a different menace - from thieves, vandals and the British weather.
Apparently, a section of the wall near to the town’s community centre is disappearing faster than it can be repaired.
Now, Town and County Councillor Bill Aron is calling for action to be taken - before a vital section of the town’s heritage and history vanishes for ever.
Coun Aron brought up the problem with the wall at a recent Town Council meeting.
He told the News: “It is sad because the wall is such an important part of our heritage. It is definitely disappearing.
“There’s no doubt some of it is down to the elements, but it does appear people are taking away pieces of the wall, especially the loose stones that have fallen off.
“These stones are disappearing before they can be put back properly.”
Coun Aron said he had already raised the matter with historical officers at the County Council.
He added he was delighted the Town Council was supporting his call for some action to be taken.
Coun Aron believes a possible solution would be to inspect and repair the walls on a regular basis.
He appeared to rule out enclosing the walls with fencing.