The Blumentritt Signal Box was previously located under the LRT Blumentritt station.
It was constructed as part of the Antipolo Extension line, the signal box/tower remained in a good condition (even survived WWII) until squatters infested the area of the railtracks in Blumentritt in the late 80s.
It was demolished during the rehabilitation of Main Line South and was replaced by a new one, ts unknown why RIHSPI didn't manage to save it unlike the Abad Santos Signal Box, the remaining structure there was the semaphore post.
- Iyo ang Tondo Kanya ang Cavite (1986).
1. Blumentritt Signal Box
2. MRR Boom Gates (Avenida/Rizal Avenue crossing)
3. Meralco Tram railtracks (going to Blumentritt St.)
4. Semaphore Signal Post
5. MRR Railtracks