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The Royal Black Preceptory is due to hold its annual demonstration in Sion Mills on Saturday, August 27th. There will be traffic delays between 9am and 6pm.
The main parade will take place at noon while feeder parades will take place in Derry/Londonderry, Strabane, Newtownstewart and Castlederg in the morning and evening.
Between 9.30am and 5pm, traffic on the A5, Omagh-bound and Strabane-bound, will be diverted at either the Peacock Road/A5 junction or Bellspark Road/A5 junction.
Lorries and buses will be diverted from the A5, through Victoria Bridge and into Strabane via Liskey Road.
Police will be deployed and will manage traffic throughout the day.