There are ancient ruins of fortresses in Tbilisi and Derbent which share a name.
In Tbilisi there is ნარიყალა Nariqala and in Derbent there is Нарын-Кала Naryn-Kala.
The story of the name ნარიყალა in Georgia is that it was given this name by the Mongols and that it means "little fortress".
The problem is that I can't find Mongolian words meaning "little" or "fortress" which resemble the words used in the name. But they also don't resemble Georgian words with those meanings.
I only found out about the similarly named fortress in Derbent because the Russian Wikipedia articles of each are linked. I haven't found a story about the name of this fortress.
Could these be now obscure Mongolian words or is it just that I'm using a dictionary from modern Mongolia and the Mongols responsible spoke a very different variety?
Or could it be that the Mongols took words from some third language to give this name? I know the Caucasus has had many rulers over the centuries.
Or could it be something else entirely?