This article explains why it is useful to maintain a road sign cadastre. It is not meant to be a full implementation manual, but rather an overview of the main reasons, the legal references, and an example of how such an inventory can be organized in a GIS.
The Italian Highway Code, through article 13, paragraph 6, establishes the road cadastre. In the quoted text, the important detail for this article is the reference to road assets, which includes signage.
Road authorities are required to establish and keep updated the cartography, the road cadastre, and their related assets according to the procedures defined by ministerial decree. The cadastre must also include the permanent systems and services connected with road traffic.
Unlike the article on the Road Cadastre, here the focus is on the highlighted part of that rule. A road sign cadastre is not explicitly named in the implementing decree D.M. LL.PP. June 1, 2001, but it clearly appears as a reference inside the attribute values for road furniture.
Why is a cartographic reference important for a road sign cadastre? Because together with the road cadastre and related assets it allows the authority to identify, at a glance, the sections of infrastructure that need new signage or maintenance, as already required by D.M. LL.PP. 24.10.2000.
The primary legal reference remains the Italian Highway Code and, in particular, article 39. Those rules can be used effectively when building a road sign cadastre inside a GIS workflow.
The images below are only demonstrative and do not claim to verify the correctness of the road-sign placement.
