Three short tributaries are known as branches or forks of the Vermilion River.
There are very few land features, other than the Vermilion River, which runs from south to north in the central part of the region.
The lake's primary inflow and outflow is the Vermilion River.
Access to the Vermilion River is provided by a boat launch.
The county was named for the southbound Vermilion River, which flows nearby.
The following counties are drained at least in part by the Vermilion River:
Vermilion River has a length of 255 km.
The Vermilion River reached a flood level of 18 feet.
There are many fish species found within the park's 22 ponds and the Vermilion River.
The bike trails wind through the forest, abandoned strip mine area, and along the Vermilion River.