"Trajan's Wall" (upper)
Not much known here but the length of 126km and that it is built not as high as the "lower" Trajan's Wall.
I indicated by a line about where it is to be looked for (reaching from the Pruth to the Dnister River.
chinoook's 1st law: Structurally weak walls tend to have double structures.
chinoook's 2nd law: Newer walls are built next older walls, not over them.
chinoook's 3rd law: Similar problems lead to similar solutions.
The most dangerous worldview is the worldview of people, who have not viewed the world. (Alexander von Humboldt (1769-1859), German naturalist and explorer)