This river runs deep within a forest. It's a small affluent of a bigger river, and it flows northward. Its 22ft across in its widest section, and around 10 to 15 feet deep. Swimming across the river is possible, but the original idea was for it to be a moderately difficult task, with a Strength (Athletics) check to avoid being swept northward and receiving a levelled amount of bludgeoning damage.
There's a partly collapsed bridge over the river. The east bank has some terrain elevations with easy to defend accesses and a great view of the surrounding area. The top height of this elevations is 30 feet, which should be quite a bit lower than the medium height of most of the trees in the forest.
The original idea for this map (which was featured in my group's ongoing 1st to 20th campaign) was for it to become the scenario for a "tactical" battle between some hobgoblins and the PCs. These hobgoblins would be divided between melee and archers, the latter quickly claiming the high ground, while the melee fighters would hostigate the PCs with polearms , while they slowly made way to the bridge, in order to create a bottleneck.