PRR Interlocking Diagrams: Philadelphia to Washington Main Line

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(Amtrak maps of this area available on Ken Reinert's Perry to Penn and Avenue to Perry pages.

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Main Line -- Philadelphia to Washington

ARSENAL, Philadelphia, Pa., M.P. ???

Ref 2, Sheet 1, 1969; 9238x2055, 268K, 200 dpi

ARSENAL, part 1 (5000x2055, 140K, 200 dpi)
ARSENAL, part 2 (5000x2055, 155K, 200 dpi)

Connection northward (RR-west) to High Line, to ZOO and New York and Harrisburg main lines. Connection eastward to Gray's Ferry Branch. Connection westward to West Chester Branch.

BRILL, Philadelphia, Pa., M.P> ?

Ref. 2, Sheet 4, 1969; 14372x1033, 152K, 200dpi

BRILL, part 1 (7399x1033, 75K, 200 dpi)
BRILL, part 2 (7399x1033, 83K, 200 dpi)

Universal interlocking. Note the varying designations of the tracks.

Map issues: "McEttvan" above 54th St. -- spelling?
At upper right, "Correct as of" is written over other text, such as when approach locking was installed and so forth. Those dates are hard to read.

BALDWIN, Eddystone, Pa. (??K, 200 dpi)

LAMOKIN, Chester, Pa. (??K, 200 dpi)

HOOK, Markus Hook, Pa. (??K, 200 dpi)

BELL, ?Claymont, Del. (??K, 200 dpi)

Connection southward to freight line, Edge Moor Yard, BRIDGE tower.

WILMINGTON, Wilmington, Del. (??K, 200 dpi)

RAGAN, ?, Del. (??K, 200 dpi)

End of the Shellpot Branch, the freight bypass around Wilmington.

DAVIS, Newark, Del. (??K, 200 dpi)

Ref 6, Sheet 6, 1962; 8281x1069, 179K, 200 dpi

DAVIS, part 1 (4283x1069, 80K, 200 dpi)
DAVIS, part 2 (4200x1069, 104K, 200 dpi)

Connection southeastward to Delmarva Secondary.

EDGEWOOD, Edgewood, Md. (??K, 200 dpi)

PERRY, Perryville, Md. (??K, 200 dpi)

Connection northwestward (RR-west) to Port Road Branch [former Columbia & Port Deposit].

BAY, Baltimore (Bay View), Md. (??K, 200 dpi)

UNION JCT., Baltimore, Md. (??K, 200 dpi)

B&P JCT., Baltimore, Md. (??K, 200 dpi)

Connection northward to Northern Central Branch.

GWYNN, Baltimore (Gwynneth? Falls), Md. (??K, 200 dpi)

GROVE, ?, Md. (??K, 200 dpi)

ODENTON, Odenton, Md. (??K, 200 dpi)

Track to the U.S. Army base at Ft. Meade branched off. Interlocking is now gone, its functions essentially replaced by present-day GROVE interlocking. GROVE's "tower" was quite literally a house trailer.

BOWIE, Bowie, Md. (??K, 200 dpi)

Connection southward to Pope's Creek Secondary.

LANDOVER, Landover, Md. (??K, 200 dpi)

Connection southward to [freight] main line to Washington D.C., RO, Richmond, Fredericksburg & Potomac RR, and "Pot"omac Yard.

Washington Union Terminal Co.

The Washinton Terminal Company rulebook (which also contains special instructions) contains the following very apt description of the WT:

The Washington Terminal Company

Comprises Union Station, the tracks from Union Station extending Northward to Division Boards located at junction with Amtrak and Washington Branch of B. & O. R.R., 467 feet north of center line of New York Avenue overhead bridge; at junction with Metropolitan Branch of B. & O. R.R., 642 feet north of center line of New York Avenue overhead bridge; Southward to the Division Board located at junction with Conrail 1,584 feet south of South Portal of First Street Tunnel; Coach Yard; and Ivy City Engine and Shop Yard.

WT diagrams have all been scanned at 300 dpi instead of the usual 200 dpi. This is because the numbers on the diagram, switch and signal numbers, are much smaller than on other diagrams. The diagrams are approximately the same size as other diagrams on this site.

WYE BRIDGE, Washington, D.C., M.P. ???

Ref 12, Sheet [5], 1978; 4194x1854, 39K, 300 dpi

This diagram shows at a greater scale some of the trackage in the vicinity of the 9th St. bridge as seen on the following diagram. This is easily seen in comparing some of the switch numbers (e.g. 602, 606, 608). However, other features seen here are not present on the following diagram.

Coach Yard, Washington, D.C., M.P. ???

Ref 12, Sheet [4], 1978; 3945x2154, 90K, 300 dpi

This is a very "busy" diagram. Lots of features are shown, and one must take care so as not to confuse the road or fence lines for tracks. Otherwise, this diagram is a wonderful study for anyone trying to model terminal facilities.

Note that the Metropolitan Branch/Subdivision of the B&O is shown in part, but that the Washington Branch/Subdivision is not, and neither is PRR trackage. The PRR is shown on the next diagram

C, Washington, D.C., M.P. ???

Ref 12, Sheet [3], 1979; 4200x2120, 84K, 300 dpi

This diagram's right end starts somewhat closer to Union Station than the southern edge of the parking lot on the previous diagram (compare locations of the 488 crossover). The diagram scanned is stamped (with an ink stamp) "issued March 1979"; the only changes are the addition of the Legend and the track designations "No. 2" and "No. 3" near the word "Amtrak".

The "Amtrak" tracks are, of course, the former PRR trackage entering the area. I surmise that PRR territory ended at the 509/511 signals, and likewise B&O territory at the 505 signal. As the WT trackage crosses underneath the substantial New York Ave. viaduct, it turns from a WSW to a SW direction.

K, Washington, D.C., M.P. ???

Ref 12, Sheet [2], 1978; 4250x2120, 84K, 300 dpi

The interlocking controlling WUT platform trackage and environs. Presently (1997) remains as an active interlocking tower.

A, Washington, D.C., M.P. ???

Ref 12, Sheet [1], 1978; x, 49K, 300 dpi

portion of 1979 revision (33K, 300 dpi)

This is the southern end of the WT. The lower level platform tracks join to enter the 1st St. Tunnel (which pass underground very near the U.S. Capitol building). The tracks exit the tunnel in a SW orientation and rise to join the PRR freight bypass (for which see Main Line--Landover to RO, immediately below).

The updated (1979) version of the diagram shows different signal symbols for the (apparently color-light) signals within the tunnels. It also adds a table showing (some) B&O signal aspects.

Map notes:

  • Signal 18LA at the south portal has a circle on the horizontal (Stop) arm; is this a typo, or does this signal have a lower right marker on it?
  • Signals 1339 and 1340 in the tunnels have filled-in quadrants, despite having numbers that would suggest these are automatics, not controlled signals.
  • "North Line of" is not completed on the original, either.
  • Does anyone know the status of "A" tower?
  • The updated map shows a filled-in marker lamp on PRR signal 24L; this is surely an ink run during printing, or a bad master.
  • An ink stamp on the updated version reads "ISSUED MARCH 1979". This is in the lower right of the diagram and is not reproduced.

Main Line -- Landover to RO

This is the freight bypass that cuts off the passenger main at LANDOVER, just north of Washington, D.C., and passes south, then west, through Washington, through the Virginia Avenue Tunnel, then after joining with the WUT trackage, to the Long Bridge across the Potomac River into Virginia and the ex-RF&P former Potomac Yard.

ANACOSTIA, Washington (Virginia Ave.), D.C. (??K, 200 dpi)

Site of a movable bridge. Just east of here, a B&O branch joined into the PRR line. Between here and VIRGINIA is the Virginia Avenue Tunnel.

VIRGINIA, Washington (Virginia Ave.), D.C. (??K, 200 dpi)

Connection, northward, to the double-track passenger line (see Washington Terminal, above).

Mark's Railroad-Related Stuff
The Broad Way: A Pennsylvania Railroad Home Page
Maps of the PRR
Interlocking Diagrams
Philadelphia to Washington: Main Line

Mark D. Bej
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