|Realms||Arnor, Arthedain, the Shire|
|Description||long, golden-brown river|
|Other names||Brandywine, Branda-nîn, Bralda-hîm|
- "And no wonder they're queer, ... if they live on the wrong side of the Brandywine River, and right akin the Old Forest. That's a dark bad place, if half the tales be true."
- ― Daddy Twofoot, A Long-expected Party
The Baranduin was a river in Eriador. To the Hobbits of the Shire, the Brandywine (as they called it) was the boundary between the known and unknown, and even those who lived in Buckland on the immediate opposite shore were considered "peculiar".
Flowing out of Lake Evendim in northern Eriador, the river flowed eastward for about 60 miles before turning generally southward; after about another 120 miles it flowed through the easternmost reaches of the Shire, forming that land's eastern border, except for Buckland, which lies east of it. Its only major crossings in the Shire are the Brandywine Bridge (originally Bridge of Stonebows) on the East Road and the Bucklebury Ferry.
Skirting the Old Forest to the south, the river then looped south-westward, crossing an old road at Sarn Ford and flowed to the north of the depopulated region of Minhiriath before flowing into the Sea to the north of the forested region of Eryn Vorn.
No tributares of the Baranduin are described except those near or in the Shire:
- The Water - central Shire, from the northwest
- The Stock-brook - arises in the Woody End
- River Shirebourn - rises in Green-Hill country, tributary is Thistle Brook
- Withywindle - from the Old Forest
- River Norbourn - in the Northfarthing
There is a Girdley Island in the river just above the Brandywine Bridge.
The name Baranduin was Sindarin for "golden-brown river", from baran and duin. The Hobbits of the Shire originally gave it the punning name Branda-nîn, meaning "border water" in original Hobbitish Westron. This was later punned again as Bralda-hîm meaning "heady ale" (referring to the colour of its water), which Tolkien renders into English as Brandywine, a word which both resembles the original Elvish name, and provides the Hobbitish meaning adequately.