On this page I have attempted to show when physical changes took place at the Junction. Where possible I've included references in the form of letters, blueprints, maps, or pictures. Sometimes though all I have to go on is word-of-mouth, or common knowledge among rail fans. Since my goal is to have this information as correct and complete as possible i am always open to corrections and additions.
| Year | Event | Reference |
| 1903 | April 6 Began Digging | Pittsburgh Press April 15, 1958 |
| 1904 | Dec. 4 First passengers carried through Tunnel. | Pittsburgh Press April 15, 1958 |
| 1906 | Administration Building constructed. | Swartz and Dawson cost sheet |
| 1906 | Connected Rt 44-48 to Shops with backtrack to avoid returns through tunnel. Included crossover but not branch to each track. | Letter in PTM files, not copied. See derail plan below. |
| 1908 | Began using P&CSRR ROW through Overbrook. | Press Releases |
| 1910 | Derails installed at south tunnel entrance, at the same time they raised watchman’s shanty | Plans, bill, and instructions. and Watchmans tower info. |
| 19?? | Added storage or team track to backtrack. Added cutback tracks. | No sure dates but there is a clue to the cutback track. |
| 1912 | P&CSRR stopped runnning. | Folklure. I don't have a reference. |
| 1916 | By this timeRoute 40 Mt. Washington was open. There are still three windows on the South end of the Admin Building. | Picture of Admin Building. |
| 1925 | Driveway from Warrington Ave. installed. | Record of track changes and memo. |
| 1927 | Connected back track to Overbrook line. | Memo and plans |
| 1928 | Double-tracked the bridge over Warrington Ave and removed spur that once connected to P&CS. | Record of track changes. |
| 1930 | Installed loop around Administration building in conjunction with the closing of Castle Shannon car house. | Memo and drawing. |
| 1931 | Removed crossover on Knoxville line. | Memos. |
| 1935 | Cutback tracks still present | School Photo |
| 1937 | Map shows two tracks to Knoxville and NO cutback tracks | 1937 map from PTM |
| 1952 | Photo still shows two lead tracks from Knoxville. | Ed Miller Photo |
| 196x | Outbound lead track had been removed | Bill Volkmer Photo |
| 195x | After 1956 the area south of Admin Building paved over to allow busses to service the Junction. | Bob Rathke and otherPhotos |
| 1975 | Paved the Tunnel to make a busway through the junction. | Photo |
| 1984 | Demolished the Admin building to make room for Light Rail. | Bob Schmidt Photo |
Modifications to the Building
I only have photographs to show the changes to the Administration Building. I am relying on photographers correct identification of dates.
|
1906 |
Bulding constructed | Swartz and Dawson cost sheet |
| Third window replaced by door and security screen installed. | Picture of Admin Building. | |
| ~1930 | Northwest corner of porch cut at angle. | I believe this was done when the loop was installed |
| after 1949 | Door on south wall returned to window and security shield removed. East porch still not enclosed. | Photo dated 1949 |
| by 1956 | Rear Porch enclosed. | Bob Rathke photo |
| by 1956 | Top roof overhang cut back. | Bob Rathke photo |
| before 1964 | Wind panels added to porch. | Early PAT Photo |
| Before 1981 | Building painted white with brown below belt rail just to make it look a little less appealing. | Bob Schmidt Photo |
| June 1984 | Building demolished. | Bob Schmidt Photo |
Things not done
| Never | I picked up some information on things that never were done, like a loop all the way around the building, double back tracks, and "Rapid Transit". | All on one page. |