The River Farset (An Fhearsaid or Abhainn na Feirste in Irish) is a river in Belfast, Northern Ireland, a tributary of the River Lagan. It is on the County Antrim side of the Lagan and joins the Lagan close to its outflow into Belfast Lough. The River Farset is now contained within a tunnel under Belfast's High Street; a tunnel supposedly big enough to take a bus. The Farset rises above Legoniel, flowed past the medieval parish church at Shankill, through Millfield and under High Street, giving that street a curving appearance, entering the Lagan to the east of the Albert Clock and High Street.