The Outer Ring Road System, or more commonly known as ORRS, is a network of major arterial roads in Singapore that forms a ring road through the towns along the city fringe. The ORRS is a semi-expressway, just like the West Coast Highway. Since 1994, roads along the ORRS have been upgraded in stages to provide a smoother route to travel across the island. Roads and interchanges along the ORRS are constantly being upgraded to cater to the ever increasing traffic demand. It starts as in Queenstown and ends as in Tampines. The series of roads passes through the areas of Queenstown, Bukit Timah, Central Catchment Nature Reserve, Bishan, Toa Payoh, Geylang and Tampines.