A glen is a valley, typically one that is long, deep, and often glacially U-shaped; or one with a watercourse running through such a valley. Whittow defines it as a "Scottish term for a deep valley in the Highlands" that is "narrower than a strath."

The word is Goidelic: gleann in Scottish and Irish Gaelic, glion in Manx. In Manx, glan is also to be found meaning glen. It is cognate with Welsh glyn. As the name of a river, it is thought to derive from the Welsh word glan meaning clean, or gleindid meaning purity.

One stunning example is the Glens of Antrim in Northern Ireland where nine glens radiate out from the Antrim plateau to the sea along the coast between Ballycastle and Larne.

In the Finger Lakes Region of New York State, the southern ends of Seneca Lake and Cayuga Lake in particular are etched with glens, although in this region the term "glen" refers most frequently to a narrow gorge, as opposed to a wider valley or strath. The steep hills surrounding these lakes are filled with loose shale from glacial moraines. This material has eroded over the past 10,000 years to produce beautiful rocky glens (e.g., Watkins Glen and Treman State Parks) and waterfalls (e.g., Taughannock Falls) as rainfall has descended toward the lakes below.

The designation "glen" also occurs often in place names such as Great Glen in Scotland, Glenrothes in Fife, Scotland, Glendalough in Republic of Ireland (Éire), Glengowrie in Australia, Glenn Norman in Canada, Glen Waverley in Australia and Glendowie in Auckland, New Zealand.

Other articles related to "glen":

Glen Donnelly
... Glen Donnelly is a fictional character from the Australian soap opera Neighbours, played by Richard Huggett ... Glen was the secret son of Jim Robinson ... Glen's most notable storyline was an inappropriate relationship with his sister, Lucy ...
Glen Donnelly - Storylines - 1990–92
... Glen turns up in Ramsay Street to see Jim and he reveals that he is his son ... Jim is shocked and Glen realises that Jim had never been aware he existed ... Jim wants to get to know Glen better and invites him to move in ...
Glen, New York - Communities and Locations in Glen
... Auries Creek – A tributary of the Mohawk in the central part of Glen ... Glen – The hamlet of Glen is in the center of the town on NY-30A ... The community was originally called "Vorheesville" and "Five Corners." The Glen Historic District was listed on the National Register of Historic Places in 2001 ...
Glen Baxter (journalist) - Career
... While still a student at Ryerson University, Glen Baxter began his career in television with a brief stint as a producer at YTV ... While at YTV, Glen also landed his first job on TV as an arts and entertainment on-camera reporter for French CBC (Société Radio-Canada) on the station’s weekly show Survolt ... In 1991, Glen received a call from Canadian television guru Moses Znaimer and landed a job at MuchMusic as an on-air reporter for FAX (now MuchNews) ...
Glen Donnelly - Development - Incest
... Glen biggest storyline was his incestuous relationship with his half-sister Lucy (Melissa Bell) ... Neither Lucy or Glen were aware that they were related after he arrived in Ramsay Street and before she returned home from boarding school ... When Glen and Lucy meet they are "unable to deny the attraction between them" ...