Thousands of people are expected to take part in Orange Order parades in the north, which get underway later today.
The first and deputy first minister have called for a peaceful and safe Twelfh of July parading season.
Arlene Foster and Martin McGuinness called for any protests to be done in a peaceful way - without undermining law and order.
Thousands of PSNI officers will be on duty throughout the province - during the day.