A GLEN is a narrow VALLEY with a stream running through it. It is a type of landscape found in Scotland, Ireland, and other parts of the British Isles. The term is derived from the Scottish Gaelic word 'gleann, ' which means 'VALLEY.' Glens are typically characterized by steep sides, a narrow opening, and a stream or river running through the middle. They are often surrounded by hills and mountains, making them a popular destination for hikers and nature lovers.