National monuments Canal and Earthen Wall eligibility?
"Het Defensiekanaal" (The Defence Canal), is a canal that runs through my hometown that was dug right before the second world war to defend against tanks in case of a german invasion. When this invasion did happen, there was heavy fighting around this canal and the rest of my hometown for a few days. Next to the canal is also an earthen wall build with earth from excavating the canal, this wall was also used in the defences. https://nl.wikipedia.org/wiki/Defensiekanaal
The canal and the earthen wall were part of a defensive line that is called the Peel-Raamstelling. Both have been granted status as national monuments by the Dutch government.
I have multiple questions about a potential nomination:
-Are these eligible without signs? At least in my hometown, there are no signs that I can find about this canal or wall specific. There are a lot of other signs about various war relics along the canal that mention them, but none about the canal or wall themselves. There is 1 sign with just the name of the canal on a bridge but the bridge itself is already a wayspot.
-If eligible, where would I drop the location? The canal is about 40 kilometers long, the wall is missing in some places but runs the same distance. At one of the 2 ends of the canal? Every town it passes through? At a bridge?
-If eligible, what happens if someone else along the 40 kilometers decides to nominate it in another location, duplicate problem?