Goose Creek, a right-hand branch of the Potomac River, is a
considerable stream, pursuing a course of about fifty miles from its
source in Fauquier County to its junction with the Potomac four miles
northeast of Leesburg. It once bore the Indian name _Gohongarestaw_,
meaning "River of Swans." Flowing northeastward across Loudoun, it
receives many smaller streams until passing the first range of
Catoctin Mountain, when it claims a larger tributary, the North Fork.
Goose Creek represents subsequent drainage dependent on the syncline
of the Blue Ridge and dating back at least as far as Cretaceous time.
Its length in Loudoun is about thirty miles, and it has a fall of one
hundred feet in the last twenty-two miles of its course. It drains
nearly one-half the county and is about sixty yards wide at its mouth.

Catoctin Creek is very crooked; its basin does not exceed twelve miles
as the crow flies, and includes the whole width of the valley between
the mountains except a small portion in the northeastern angle of the
County. Yet its entire course, measuring its meanders, would exceed
thirty-five miles. It has a fall of one hundred and eighty feet in the
last eighteen miles of its course, and is about twenty yards wide near
its mouth.

The Northwest Fork rises in the Blue Ridge and flows southeastward,
mingling its waters with the Beaver Dam, coming from the southwest,
immediately above Catoctin Mountain, where their united waters pass
through a narrow valley to Goose Creek.

Little River, a small affluent of Goose Creek, rises in Fauquier
County west of Bull Run mountain and enters Loudon a few miles
southwestward of Aldie. It pursues a northern and northeastern course