Shirebourn

A lesser river of the Shire's Eastfarthing, whose name means simply 'Shire-stream'. Its source was in the uplands of the Green Hill Country, from where it flowed south and then southeast. At Willowbottom, it met the Thistle Brook, and then flowed eastwards until the Shirebourn itself met the Brandywine.

The Shirebourn flowed into the Brandywine beneath Deephallow, and at its mouth formed the boggy region known as the Overbourn Marshes, opposite the southern end of the High Hay.