The wide road continues north where it joins the Raglan Battery Shelter. The tunnel would allow military lorries to travel within the Rock. The Great North Road ends at the now abandoned Calpe Hole Generating station however, the tunnel system continues all the way to the north face of Gibraltar where the World War II tunnels join the Galleries dug out during the latter part of the 18th century, now known as the Great Siege Tunnels. With the addition of Fosse Way in 1944 it was also possible to travel from the tunnel system within the Northern Defences down the complete length of the Rock to emerge on the south east side of Gibraltar.