Portmore Lough is a small lake in southwest County Antrim

County Antrim

County Antrim is one of six counties that form Northern Ireland, situated in the north-east of the island of Ireland. Adjoined to the north-east shore of Lough Neagh, the county covers an area of 2,844 km², with a population of approximately 616,000...

, Northern Ireland

Northern Ireland

Northern Ireland is one of the four countries of the United Kingdom. Situated in the north-east of the island of Ireland, it shares a border with the Republic of Ireland to the south and west...

 that drains water into nearby Lough Neagh

Lough Neagh

Lough Neagh, sometimes Loch Neagh, is a large freshwater lake in Northern Ireland. Its name comes .-Geography:With an area of , it is the largest lake in the British Isles and ranks among the forty largest lakes of Europe. Located twenty miles to the west of Belfast, it is approximately twenty...

. It is roughly circular and covers an area of 286 hectares. The Lough and its shoreland is designated a Ramsar site, a Special Protection area (SPA) and an Area of Special Scientific Interest (ASSI).

The lough is near the site of the former Portmore Castle, erected in 1664 and removed in 1761. It is also the presumed location of the Portmore Ornament Tree whose demise in a windstorm of 1760 is lamented in the Irish folk song, "Bonny Portmore

Bonny Portmore

"Bonny Portmore" is an Irish traditional folk song which laments the demise of Ireland's old oak forests, specifically The Great Oak of Portmore, which fell in a windstorm in 1760 and was subsequently used for shipbuilding and other purposes....

." One source refer to Portmore Lough as Lough Beg (Loch Bheag, or "small lake"), which is an alternative name for the same lough.