From A Wiki of Ice and Fire
The Honeywine is a large river in the Reach. Beginning near Brightwater Keep, it flows south and is joined by a tributary at Honeyholt, then continues south to Oldtown where it is joined by a tributary originating to the east by Uplands. It then flows into Whispering Sound at southern Oldtown. The Honeywine is the agricultural capital of the Reach.
During the Dance of the Dragons, the river was the site of the Battle on the Honeywine, which resulted in a victory for the greens against the blacks.
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