An SD40-2. A GP40, and two SD40’s wait for a signal at Belt Line Junction near Reading, Pennsylvania. Belt Line Junction is an “X”-shaped plant. The train seen here is on the main line from downtown Reading, while the tracks to the right are the Reading Belt Line. At the west (geographically north) end of the junction, the Blandon Low Grade to Allentown, diverges from the main line (now the R&N) to the anthracite regions.