Numbering of roads in Spain (1940)

This map appears in the General Plan for Public Works, published by the Spanish Ministry of Development in 1940. The plan is commonly known as the Peña Plan, taking its name from the Minister of Development at the time, Alfonso Peña Boeuf, although in reality the plan was drawn up by the engineer Victoriano Muñoz Oms.

The illustration describes how, starting in 1940, all roads and motorways in Spain's national network began to be numbered. The six radial motorways leading out of Madrid and reaching the ends of the Iberian Peninsula were defined as the main ones, numbered from one to six, following a clockwise direction.

With this in mind, the numbering of the remaining roads follows the following three-digit pattern:

• The first number identifies the region where the road begins.
  • From 1 to 6 for each of the regions located between two of the radial roads.
  • The number 7 was reserved for the Balearic Islands.
  • 8 for the Canary Islands
  • 9 for Spain's possessions in Africa (still significant in 1940).
• The second number further defined the specific region.
  • In the case of roads on the peninsula, it shows how close to Madrid the road begins, taking one hundred kilometres for each number.
  • In the Balearic Islands, each number refers to an island.
    • 71 – Majorca.
    • 72 – Menorca.
    • 73 – Ibiza.
    • 74 – Formentera.
  • In the Canary Islands, each number refers to an island.
    • 81 – Gran Canaria.
    • 82 – Tenerife.
    • 83 – La Palma.
    • 84 – La Gomera.
    • 85 – Lanzarote.
    • 86 – Fuerteventura.
    • 87 – El Hierro.
• Finally, the third number indicates the address.
  • Roads ending in an odd number indicate a radial direction. That is, those that lead to or away from Madrid. In the case of the islands, towards the centre of the island.
  • Roads ending in an even number indicate a ring road, either on the mainland or on any of the islands.

The numbering with 9 was lost with the loss of possessions in Africa, as Ceuta and Melilla no longer use this identification. The rest of the numbering is still in force.

Sources

• The roads of Extremadura – Plan Peña