The One Ring: Fellowship of the New Alliance
As the River Gladden spills into the Anduin, it creates a water-logged landscape of ponds, little slow-flowing channels and marshes called the Gladden Fields. The marshes are not especially perilous or unpleasant — this land knew the Elves, long ago, and their blessing lingers here. In summer, the fields become fields of gold and streams of silver as flowers bloom on the banks and fish leap in the waters.
These marshes have always been deserted. No great kingdoms ever claimed the region, so it has always been left to the poor and the forgotten. For much of the Third Age, Hobbits lived in the Gladden Fields. Eventually, most of them migrated over the mountains into Eriador, but the Marshes were never wholly abandoned. As the Shadow grew in Mirkwood, agents of the Enemy occupied the Gladden Fields, driving out the existing residents. The presence of Orcs and other fell beasts has not diminished the beauty of this land, but make it even more dangerous.