[3] Lough Gill has a unique microclimate and is noted for its high number of rare or scarce animal and plant species.

It is part of the Lough Gill SAC (Special Area of Conservation) for habitats listed on Annex I and II of the E.U.

In a scientific study, Arbutus unedo pollen was found at Slish Lake dating from as early as 100 AD, and so it is considered native to this area.

The shores of the lake are home to the world's northernmost specimens of the rare Mediterranean strawberry tree (Arbutus unedo).

The lake shore and surroundings support several rare plant species, including yellow bird's-nest (Monotropa hypopitys), lady's mantle (Alchemilla glaucescens), ivy broomrape (Orobanche hederae), black bryony (Tamus communis), intermediate wintergreen (Pyrola media) and bird's-nest orchid (Neottia nidus-avis).

"Bright Gile, Romra's daughter, to whom every harbour was known, the broad lake bears her name to denote its outbreak of yore.

While the modest maiden was washing in the unruffled water of the pool, she sees on the plain tall Omra as it were an oak, lusty and rude.

Her nurse came and bent over her body and sat her down yonder in the spring: as she keened for Gile vehemently, she fell in a frenzy for the girl.

As flowed the tears in sore grief for the maiden, the mighty spring rose over her, till it was a vast and stormy lake.

It is run by a committee made up of local swimmers and friends of the family of Neill McGarry, for whom the event trophy is dedicated.