This map, published by the Directorate General of Telegraphs in 1867, with the title Telegraphic Letter from Spain, shows the extent of the telegraph network in Spain in 1867.
Spain's telegraph network was inaugurated in 1854, with the first line connecting Madrid and Irún, as well as connecting the country to France's existing telegraph network. A year later, in 1855, a plan was drawn up to extend the telegraph from Madrid to all provincial capitals, which was completed in 1864.
This map shows how the main network is centralised, but some cross-country lines are also beginning to appear, the most important being those along the Cantabrian coast, the Mediterranean coast and the Vía de la Plata. Some lines that were still in operation are also shown with a dotted line, such as the one connecting Albacete and Murcia, the one from Ciudad Real to Mérida and the one connecting Málaga and Almería.
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