[2] The River Blackwater enters Lough Neagh west of Derrywarragh Island and is navigable from Maghery to Blackwatertown.

[3] In 1575, during the Tudor conquest of Ireland, the English built a fort at what is now Blackwatertown, to control this important river crossing in the heart of Gaelic Ulster.

In February 1595, at the outset of the Nine Years' War, a Gaelic force led by Art MacBaron O'Neill assaulted and captured the fort from the English.

[4] The wider townland is also called Lisbofin, from Lios Bó Finne meaning "fort of the white cow",[4] which may refer to one of the ringforts in the area.

[citation needed] The local GAA club, Port Mór, plays at Junior level in county competitions.