I found this on the internet – a timetable or schedule for trains bound for what are now destinations in Rizal (e.g., Antipolo, Taytay, San Mateo and Montalban). Pasig and Marikina used to be part of Rizal province with the capital at Pasig (thus, Kapitolyo).
From the schedule, one can see that the main line was between Manila and Pasig (Rosario). From Rosarion, the line branched out towards either Antipolo or Montalban (now Rodriguez). Certain trains like Nos. 41, 45, 47, 51 and 56 terminated in Antipolo while others at Montalban. Again, one cannot help but wonder what if these lines were sustained and still operational (of course, upgraded) today. Commuting would have been different for many of us residing in Rizal and along these lines.