Complex sentence: When County Coleraine was created in 1585, its administration was meant to be carried out in the town of Coleraine, however the jail and courthouse were built in Desertmartin, the centre of the Barony of Loughinsholin, which then lay in neighbouring County Tyrone.
Split into simpler sentences: When County Coleraine was created in 1585, its administration was meant to be carried out in the town of Coleraine. However, the jail and courthouse were built in Desertmartin, the middle of the Barony of Loughinsholin, which then lay in neighbouring County Tyrone.