Allan Water

The Allan Water is a river in central Scotland. Rising in the Ochil Hills, it runs through Strathallan to Dunblane and Bridge of Allan before joining the River Forth. It is liable to cause floods in lower Bridge of Allan.
It shares its name with a tributary of the River Teviot. The name is similar to the Ale Water in Berwickshire, the River Alness in Ross-shire, the Allander Water in Stirlingshire, the River Alne and the Ayle Burn in Northumberland, the River Ellen in Cumbria, and several names in the south of England, Wales and Cornwall. Ptolemy, who wrote his Geography about 150 AD, gave the names of some of these rivers as Alauna or Alaunos. Ekwall says that Alauna or Alaunos are British [i.e. Brythonic or P-Celtic] river names. Nicolaisen says that the name Allan is of Pre-Celtic Indo-European origin. Its original form was Alauna, from the Indo-European root *el-/ol-, meaning "to flow, to stream". Several European rivers and settlements have names that may come from that root. Others say that Alauna was a Celtic river goddess, also found in Brittany; Alaunus was a Gaulish god of medicine and prophesy.

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