History and Comprehensive Description of Loudoun County, Virginia. James William Head
be in force from and after the passing thereof.
As at present bounded, the old channel at the mouth of Sugar Land run, at Lowe's Island,[3] is "the commencement of the line that separates Loudoun from Fairfax County and runs directly across the country to a point on the Bull Run branch of Occoquan River, about three eighths of a mile above Sudley Springs, in Prince William County." The Bull Run then forms the boundary between Loudoun and Prince William to its highest spring head in the Bull Run mountain, just below the Cool Spring Gap. The line then extends to the summit of the mountain, where the counties of Fauquier and Prince William corner. From the summit of this mountain, a direct line to a point[4] on the Blue Ridge, at Ashby's Gap, marks the boundary between Loudoun and Fauquier counties. A devious line, which follows in part the crests of the Blue Ridge until reaching the Potomac below Harpers Ferry, separates Loudoun from Clarke County, Virginia, and Jefferson County, West Virginia, on her western border. The Potomac then becomes the dividing line between Loudoun County, and Frederick and Montgomery counties, Maryland; "and that State, claiming the whole of the river, exercises jurisdiction over the islands as well as the river."
[3] "What is called Lowe's Island, at the mouth of Sugarland Run, was formerly an island, and made so by that run separating and part of it passing into the river by the present channel, while a part of it entered the river by what is now called the old channel. This old channel is now partially filled up, and only receives the waters of Sugarland Run in times of freshets. Occasionally when there is high water in the river the waters pass up the present channel of the run to the old channel, and then follow that to the river again. This old channel enters the river immediately west of the primordial range of rocks, that impinge so closely upon the river from here to Georgetown, forming as they do that series of falls known as Seneca Falls, the Great, and the Little Falls, making altogether a fall of 188 feet in less than 20 miles."—Memoir of Loudoun.
[4] Designated in an old record as a "double-bodied poplar tree standing in or near the middle of the thoroughfare of Ashby's Gap on the top of the Blue Ridge." It succumbed to the ravages of time and fire while this work was in course of preparation.
This completes an outline of 109 miles, viz: 19 miles in company with Fairfax, 10 with Prince William, 17 with Fauquier, 26 with Clarke and Jefferson, and 37 miles along the Potomac.
TOPOGRAPHY.
Loudoun County is preeminently a diversified region; its surface bearing many marked peculiarities, many grand distinctive features. The broken ranges of hills and mountains, abounding in Piedmont Virginia, here present themselves in softly rounded outline, gradually sinking down into the plains, giving great diversity and picturesqueness to the landscape. They are remarkable for their parallelism, regularity, rectilineal direction and evenness of outline, and constitute what is by far the most conspicuous feature in the topography of Loudoun. Neither snow-capped nor barren, they are clothed with vegetation from base to summit and afford fine range and pasturage for sheep and cattle.
The main valleys are longitudinal and those running transversely few and comparatively unimportant.
The far-famed Loudoun valley, reposing peacefully between the Blue Ridge and Catoctin mountains, presents all the many varied topographic aspects peculiar to a territory abounding in foothills.
The Blue Ridge, the southeasternmost range of the Alleghanies or Appalachian System presents here that uniformity and general appearance which characterizes it throughout the State, having gaps or depressions every eight or ten miles, through which the public roads pass. The most important of these are the Potomac Gap at 500 feet and Snickers and Ashby's Gap, both at 1,100 feet. The altitude of this range in Loudoun varies from 1,000 to 1,600 feet above tide-water, and from 300 to 900 feet above the adjacent country. It falls from 1,100 to 1,000 feet in 4 miles south of the river, and then, rising sharply to 1,600 feet, continues at the higher series of elevations. The Blue Ridge borders the county on the west, its course being about south southwest, or nearly parallel with the Atlantic Coast-line, and divides Loudoun from Clarke County, Virginia, and Jefferson County, West Virginia, the line running along the summit.
Of nearly equal height and similar features are the Short Hills, another range commencing at the Potomac River about four miles below Harpers Ferry and extending parallel to the Blue Ridge, at a distance of nearly four miles from summit to summit, for about twelve miles into the County, where it is broken by a branch of Catoctin Creek. Beyond this stream it immediately rises again and extends about three miles further, at which point it abruptly terminates.
A third range, called "Catoctin Mountain," has its inception in Pennsylvania, traverses Maryland, is interrupted by the Potomac, reappears in Virginia at the river margin, opposite Point of Rocks, and extends through Loudoun County for a distance of twenty or more miles, when it is again interrupted.
Elevations on Catoctin Mountain progressively diminish southward from the Potomac River to Aldie, although the rocks remain the same, and the Tertiary drainage, which might be supposed to determine their elevations, becomes less effective in that direction.
Probably this mountain does not exceed an average of more than 300 feet above the surrounding country, though at some stages it may attain an altitude of 700 feet. Rising near the Potomac into one of its highest peaks, in the same range it becomes alternately depressed and elevated, until reaching the point of its divergence in the neighborhood of Waterford. There it assumes the appearance of an elevated and hilly region, deeply indented by the myriad streams that rise in its bosom.
On reaching the Leesburg and Snicker's Gap Turnpike road, a distance of twelve miles, it expands to three miles in width and continues much the same until broken by Goose Creek and its tributary, the North Fork, when it gradually loses itself in the hills of Goose Creek and Little River, before reaching the Ashby's Gap Turnpike.
The Catoctin range throughout Loudoun pursues a course parallel to the Blue Ridge, the two forming an intermediate valley or baselevel plain, ranging in width from 8 to 12 miles, and in altitude from 350 to 730 feet above sea level. Allusion to the physiography of this valley—so called only by reason of its relation to the mountains on either side—has been made elsewhere in this department.
Immediately south of Aldie, on Little River, near the point of interruption of Catoctin Mountain, another range commences and extends into Fauquier County. It is known as "Bull Run Mountain," but might rightly be considered an indirect continuation of the elevation of the Catoctin, its course and some of its features corresponding very nearly with that mountain save only that it is higher than any of the ranges of the latter, excepting the western.
East of the Catoctin the tumultuous continuity of mountains subsides into gentle undulations, an almost unbroken succession of sloping elevations and depressions presenting an as yet unimpaired variety and charm of landscape. However, on the extreme eastern edge of this section, level stretches of considerable extent are a conspicuous feature of the topography.
Three or four detached hills, rising to an elevation of 150 or 200 feet above the adjacent country, are the only ones of consequence met with in this section.
COMPARATIVE ALTITUDES.
The hilly character of Loudoun is clearly shown by the following exhibit of the elevation of points and places above tide-water. The variations of altitude noted in this schedule are based upon conflicting estimates and distinct measurements made at two or more points within a given circumference and slightly removed one from the other.
| Feet. | ||||
| Sterling | 415 | |||
| Ashburn |