Romulo

Overview

Romulo is a domestic submarine cable system connecting two landing points within Spain. Spanning 237 kilometres, it serves an intra-Spanish corridor in the western Mediterranean, linking the Spanish mainland to the Balearic Islands region. The cable is owned and operated by Red Electrica, the Spanish electricity transmission system operator.

Route and Landings

Both landing points are located in Spain. The cable comes ashore at Sagunto, on the eastern coast of the Spanish mainland near Valencia, and at Santa Ponsa, situated on the island of Mallorca in the Balearic Islands. These two termination points define a relatively short cross-sea span of 237 kilometres across the western Mediterranean.

Ownership and Operators

Romulo is wholly owned by Red Electrica, the state-affiliated company responsible for operating Spain's high-voltage electricity transmission network. Red Electrica's involvement in submarine cable infrastructure reflects its broader mandate to ensure reliable interconnection between mainland Spain and the Spanish island territories.

Status and Timeline

Romulo entered service in 2011 and is currently operational. It represents a relatively early example of modern intra-Spanish submarine connectivity infrastructure between the mainland and the Balearic Islands.

Regional Context

Spain's coastline anchors a wide range of submarine cable systems in the Mediterranean and beyond. Among the cables sharing Spanish landings, most are long-haul international systems: 2Africa extends approximately 45,000 kilometres and reached service in 2024, while the Africa Coast to Europe (ACE) system spans some 17,000 kilometres and entered service in 2012. Several further international cables — including Medusa, Sol, Anjana, and Grace Hopper — are either recently completed or planned, ranging from roughly 7,000 to 8,800 kilometres in length. Romulo, at 237 kilometres, is distinct from all of these as a short domestic link rather than a transoceanic or inter-regional system, serving a specific intra-national connectivity function within Spanish territory.

Strategic Role

By connecting Sagunto on the Spanish mainland with Santa Ponsa on Mallorca, Romulo provides a direct subsea link between the Iberian Peninsula and the Balearic Islands. Its operation under Red Electrica situates it within Spain's national infrastructure framework, supporting connectivity across the western Mediterranean portion of Spanish territory. The cable's relatively short length and single-country scope distinguish it clearly from the international systems that also land in Spain.