This branch was connected to another UP branch, from Los Angeles to Glendale, and had a lot of street trackage, much of it in long-established business districts and neighborhoods that have not been redeveloped.
The branch curved east from the junction on the east bank of the Los Angeles River, and almost immediately entered Humboldt St. for several blocks of street running. The Humboldt St. section was the last part abandoned (1970s) but the track remained intact until at least 1982. There are several sidings still in place in the street, but all of the industrial buildings appear to be abandoned. East of Humboldt St. the track paralleled the The Second District of the AT&SF for the first of three bridges over the Arroyo Seco Parkway (LA's first freeway, opened around 1940). Once across the bridge the tracks ran parallel to the Santa Fe a few blocks to the east, then crossed the Santa Fe at grade near Highland Park. Further east the track entered York Blvd. for the second Arroyo Seco Pkwy crossing, then entered South Pasadena. The track paralleled Arroyo Drive then turned east and ran down the center of Grevelia St. for a few blocks. The track then turned northeast and paralleled the Santa Fe for the third crossing of the Arroyo Seco Pkwy. The track continued on next to the Santa Fe for a few more blocks, passed the site of "Raymond", then turned north and west to Pasadena and ultimately Linda Vista.
Very little of the right of way an be found within Pasadena city limits, as that area has been updated with new buildings. Much of the end section near Linda Vista is now used by freeways. Except for the street trackage in the top left photo, most of this line was abandoned by the 1960s.