In January of this year, I took my first steps toward building a roster (or at least the start of a plan for one). Using information in timetables from the B&O and P&LE, I compiled a spreadsheet listing the passenger and commuter trains using the P&LE terminal in 1949, including their scheduled times, direction, origination, destination and train numbers. With this information gathered in one place, I determined that the 40 daily arrivals and departures could be simulated with just 14 model trains, like actors playing multiple parts in a play. I was also able to identify how many storage tracks would be needed in the terminal scene and in the east and west staging yards, if all trains were to be modeled. I also decided to plan for two types of operating sessions: a day session for terminal arrivals and departures between 6:00 am and 5:30 pm and a night session for arrivals and departures between 8:30 pm and 4:00 am (there were no trains scheduled between 4 and 6 am). With a 3:1 fast clock, the 11.5-hour, 24-train day session would take about 4 hours, and the 7.5-hour, 16-train night session would take 2.5 hours.