A huge underwater tunnel connecting Europe to Africa could finally become a reality after scientists announced that the engineering project is possible. The landmark undertaking, which would see the tunnel pass under the Strait of Gibraltar, has once again been revived by Spain, having been proposed by various administrations for decades.

A study commissioned by the Spanish Government and conducted by German tunnel specialists Herrenknecht concluded in October that drilling a railway tunnel below the Strait would be technically feasible using today’s technology. Since then, authorities have tasked Spanish consultancy Ineco with drafting a blueprint for the project by the end of next year, with hopes that Government approval could come as early as 2027.

The idea of building a man-made connection between Europe and Africa was first proposed in the 1970s, making sporadic appearances in electoral campaigns and Government agendas since then, but no concrete steps have been taken until now. Previous proposals included the formation of a joint Spain-Morocco committee in 1979 to study the feasibility of the plan.

The tunnel, to be bored beneath the nine-mile stretch of water separating southern Spain from Morocco, would be loosely modelled on the Eurotunnel, which opened in 1994 and connects Britain to northern France beneath the English Channel.

Featuring two parallel railway tunnels, each carrying trains in one direction, the project would likely link Punta Paloma in Cadiz with Morocco’s Cape Malabata, near Tangier. The total length of the tunnel would be approximately 26 miles, with nearly 17 miles of the route running underwater. It is also expected to exceed a depth of 1,540 feet – far deeper than the Channel Tunnel, whose deepest point is only 246 feet below sea level.

Once completed, the crossing is estimated to take around 30 minutes by train, with the capacity to transport both passengers via high-speed AVE trains and freight.

If approved, fieldwork is expected to begin in 2030, with the main construction phase scheduled between 2035 and 2040. However, these dates are subject to change.

The current route, between Punta Paloma and Cape Malabata, is the result of decades of scrapped proposals, which also included an early idea of a suspension bridge. However, this kind of connection was abandoned due to the Strait’s depth, seismic activity and extreme wind conditions.

Some estimates suggest it will cost £6 billion, though other estimates have put it between £42 and £84 billion, depending on the design.