Comes from Loch a'Ghartain Steve!
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Place-Names of the Cairngorms National Park
2013 photos & vids here
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Many thank Wendy. I’ve often asked on my visits regarding the name. However, it would seem that whoever I asked did not have the knowledge. I guess 'Ghartain' is a Gaelic name, and Garten is easier to say. I thought it rather strange a German name associated with the Glens of Scotland.
Steve it was originally a settlement called Gart and changed in 1860s to become Boat of Garten after the ferry that crossed the spey.
How fascinating Lmac, thank you for the information! I have found an interesting link which refers to it.
Birdie's DU Summaries 2018 https://www.imagicat.com/