[2] It is about 10 kilometres (6.2 mi) long from its head at Invercreran to its mouth on the Lynn of Lorne, part of Loch Linnhe.

The loch narrows and becomes shallower at both Eriska and Creagan, meaning that tidal currents are accelerated through these points.

Between these shallow zones lie deeper basins in which the water is more still, proving a habitat for Norway lobster and seapen.

[7] At the head of Loch Creran lies the Glasdrum Wood national nature reserve,[8] an internationally important atlantic oakwood managed by Scottish Natural Heritage, classified as both a Special Area of Conservation and a Site of Special Scientific Interest.

This predominantly ash and oak woodland is home to butterflies like the rare chequered skipper,[9] as well as being frequented by otters.