Hillsborough Castle is an official government residence in Northern Ireland. It is the official residence of the Secretary of State for Northern Ireland, and the official residence in Northern Ireland of the British monarch and other members of the British royal family when they visit the region, as well as a guest house for prominent international visitors.
From 1924 until the post's abolition in 1973, it was the official residence of the governor of Northern Ireland. Since April 2014, it has been managed by Historic Royal Palaces, and is open to the paying members of the public.
Wikipedia https://en.wikipedia.org/wiki/Hillsborough_Castle
Official website http://www.hrp.org.uk/aboutus/whoweare/hillsborough-castle
Email Hillsboroughcastle@hrp.org.uk
Phone +44 28 9268 1300
Address The Square, Hillsborough, BT26 6AG, UK
Coordinates 54°27'40.565" N -6°5'9.323" E