Oman has two expressway grade highways, with the first 8 lane expressway set to open in 2017. Al Batinah Coastal Road runs along the Batinah Coast of the Sea of Oman. It forks near Shinas, with one leading inland to Wadi Hatta and another to Fujairah. The speed limit is generally 120 km/h. In the Muscat area, this highway is known as Sultan Qaboos Street, and it is the trunk road running through the city. Outside the Muscat area, the interchanges take the form of roundabouts spaced approximately 7 km apart. Each roundabout contains unique features to enliven the streetscape. The roundabouts are named for driver navigation. There are no mainline railways in Oman, but some are planned, including links to adjacent countries. The narrow gauge Al Hoota Cave Train takes tourists into the cave complex in a journey of 4 minutes and distance of 400m. The estimated total length of the Oman National Railway network is 2,135km. It is divided into several segments linking Oman's borders with the UAE to Muscat, as part of the GCC Railway Network and also to the southern parts of the country - Port of Al Duqm, the Port of Salalah and the Yemen border.