and accounts for 1.8% of GDP. The country currently has no UNESCO World Heritage Sites, but it has eight declared tentative sites for UNESCO inclusion since 2012. These sites include: Ancient Ruin of Drukgyel Dzong, Bumdelling Wildlife Sanctuary, Dzongs: the centre of temporal and religious authorities (Punakha Dzong, Wangdue Phodrang Dzong, Paro Dzong, Trongsa Dzong and Dagana Dzong), Jigme Dorji National Park (JDNP), Royal Manas National Park (RMNP), Sacred Sites associated with Phajo Drugom Zhigpo and his descendants, Sakteng Wildlife Sanctuary (SWS), and Tamzhing Monastery. Bhutan also has numerous tourist sites that are not included in its UNESCO tentative list. Bhutan has one element, the Mask dance of the drums from Drametse, registered in the UNESCO Intangible Cultural Heritage List. Transport Air Paro Airport is the only international airport in Bhutan. National carrier Drukair operates flights between Paro Airport and Bathpalathang Airport in Jakar (Bumthang Dzongkhag), central Bhutan, Gelephu Airport in Gelephu (Sarpang Dzongkhag) in the south and Yongphulla Airport in the east (Trashigang Dzongkhag) on a weekly basis. Road The Lateral Road is Bhutan's primary east–west corridor, connecting the towns of Phuentsholing in the southwest to Trashigang in the east. Notable settlements that the Lateral Road runs through directly are Wangdue Phodrang and Trongsa. The Lateral Road also has spurs connecting to the capital Thimphu and other population centers such as Paro and Punakha. As with other roads in Bhutan, the Lateral Road presents serious safety concerns due to pavement conditions, sheer drops, hairpin turns, weather, and landslides. Since 2014, road widening has been a priority across Bhutan, in particular for the north-east–west highway from Trashigang to Dochula. The widening project is expected to be completed by the end of 2017 and will make road travel across the country substantially faster and more efficient. In addition, it is projected that the improved road conditions will encourage more tourism in the more inaccessible eastern region of Bhutan. Currently, the road conditions appear to be deterring tourists from visiting Bhutan due to the increased instances of road blocks, landslides, and dust disruption caused by the widening project. Rail Although Bhutan currently has no railways, it has entered into an agreement with India to link southern Bhutan to India's vast network by constructing an , broad gauge rail link between Hashimara in West Bengal and Toribari in Bhutan. The construction of the railway via Satali, Bharna Bari and Dalsingpara by Indian Railways