It seems there is very little info on a small railroad that did big things...

the C&P's 175th anniversary this year, I was trying to recreate all the locomotives in a simulation for this event, but I was suffering from a lack of diagrams and photos, I came here to ask if anyone had anything on the RR info, photo, or diagram wise (including the loco works and WM's ownership of the line).

Cumberland & Pennsylvania
(The follow account of the C&P was written by author Alan Kandel.)

“On January 2, 1854 the Mt. Savage Iron Company conveyed to the Cumberland and Pennsylvania Railroad Company the main track from Cumberland to Borden Yard via the Mt. Savage wye, a length of 14 miles, and the Potomac Wharf branch to the canal (the Chesapeake & Ohio canal), 0.9 miles long, wrote Deane Mellander in “Cumberland and Pennsylvania Railroad: Western Maryland’s Historic Coal Carrier.” And it was at this juncture that “the C&P was finally in business for real” (Mellander, Deane, 1981, p. 7). Mt. Savage Iron though, shortly thereafter became the target of a take-over and in March 1860 fell into the hands of Consolidation Coal Company and by virtue of this, CCC, all of a sudden, found itself in the railroad business.

At its height in 1906, the railroad itself that year hauled no less than 4.3 million tons of western Maryland-mined semi-bituminous coal to its customers, that and/or was transferred to a connecting railroad for delivery elsewhere. And there was plenty of that to be had.

A precipitous decline in the amount of coal being mined in the area starting circa the 1920s – the “bread & butter” of C&P’s operation and primary reason for being – spelled the beginning of the end for this 97.4-mile pike. By 1922, a strike year, production was down considerably, C&P shipping just 530,000 tons. A brief recovery occurred in 1923 when 1.2 million tons were moved which was then bested by 400,000 tons more hauled in 1926. The recovery was indeed short-lived as indicated by the million tons delivered in 1930. That the depression was just around the corner didn’t help.

Beset with its own financial problems, Consolidation Coal during the early ‘40s was searching for a buyer. For $1.1 million, through Interstate Commerce Commission approval, ownership of the railroad was transferred to the Western Maryland Railway on May 3, 1944, one of three railroads the C&P interchanged freight with. This was the first time in its more than 100-year history C&P was owned by a bona fide railroad company. It’s extremely ironic that just nine-and-a-half years’ hence, the C&P name would be permanently retired (Mellander, Deane, 1981, pp. 16-17).

Incidentally, like that of its contemporaries, the railroad also had a hand in the passenger train transportation realm. However, by the 1920s, passenger revenues were beginning to dry up. By mid-year 1942, the railroad decided the passenger service should be discontinued. Even though the “‘road had its share of derailments, wrecks, and boiler explosions,” as Mellander pointed out, it “apparently never had a passenger fatality in 99 years, an enviable record for any railroad (Mellander, Deane, 1981, p. 11).

“Railroads like the C&P, in spawning the American Industrial giant of the 20th Century, sowed the seeds of their own demise,” the author reasoned. As fate or luck would have it, the “C&P was born in the iron age, grew up and prospered in the coal age, and almost died in the atomic age,” which is what probably would have happened if the right buyer offering the right price didn’t come along when it did. Ah, it was all in a century’s work.

Cumberland and Pennsylvania map notes
https://korns.org/misc/CPRR-map-38/CPRR ... Cumberland & Pennsylvania Railroad
This 1938 map shows the configuration of the Cumberland & Pennsylvania Railroad in 1938. It was provided by Mike McKenzie. It is included here because it shows items of interest regarding the area near Wellersburg, PA and Barrelville, Maryland. Of particular interest is the fact that the branch Barrelville Branch railroad to Wellersburg is still being identified in 1938. This inclusion is curious, because that branch railroad appears to be abandoned in a 1939 USDA aerial photo.
The map also identifies some local area mines. Mike thinks, but isn't sure, that these mines may have been located as follows:
The #4 Kennell Coal Company may have been located out along West Mineral Street, across the road from where the old office sets
the #3 Rowe Brothers mines may have been located on the east side of Mineral Street about 1/8 mile from Route 160, just a little north west of the present day fire department. The owner there had inquired about filling in the old mine remains.
Mike indicates that the #4 Georges Creek Barrelville Coal Co. Parker mine is believed to have been near the bend in the Barrelville road, on the east side of the north branch of Jennings Run, behind the now-abandoned Curry Lumber Co. saw mill.