text: Ahead of the main procession, marchers and bands paraded around the city's historic walls.
  It is one of the biggest parades held in Northern Ireland and marks the anniversary of the ending of the Siege of Derry in 1689.
  Thousands of supporters from across the UK turned out to watch the 145 bands taking part.
  Having completed a circuit of the walls, members of the Apprentice Boys made their way to the Diamond for a wreath laying ceremony.
  A thanksgiving service, "to give thanks to God for the deliverance of the city," was then held at St. Columb's Cathedral.
  The memorial ceremony is held on the second Saturday in August each year, to commemorate the ending of the 105-day siege of the city in August 1689.
  Also known as William of Orange, or King Billy, the new monarch was supported by Protestants in Derry, who shut the gates of the walled city to keep out the advancing Jacobite army.
target: The annual Apprentice Boys demonstration has taken place in Londonderry.