Glaslough (/ɡlæsˈlɒx/ glas-LOKH; Irish: Glasloch, meaning 'green lake')[2] is a village and townland in the north of County Monaghan, Ireland, on the R185 regional road 3 km (2 mi) south of the border with Northern Ireland and 10 km (6 mi) northeast of Monaghan town.

[3][4] Castle Leslie, a large Victorian country house and luxury hotel, is located on the edge of the village.

The partition of Ireland in 1922 turned the boundary with County Armagh into an international frontier, after which trains were routinely delayed by customs inspections.

In 1957, the Government of Northern Ireland made the GNR board close the line between Portadown and the border, giving the board no option but to withdraw passenger services between the border and Clones as well.

This article related to the geography of County Monaghan, Ireland is a stub.